Commit | Line | Data |
---|---|---|
c9de560d AT |
1 | /* |
2 | * Copyright (c) 2003-2006, Cluster File Systems, Inc, info@clusterfs.com | |
3 | * Written by Alex Tomas <alex@clusterfs.com> | |
4 | * | |
5 | * This program is free software; you can redistribute it and/or modify | |
6 | * it under the terms of the GNU General Public License version 2 as | |
7 | * published by the Free Software Foundation. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public Licens | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111- | |
17 | */ | |
18 | ||
19 | ||
20 | /* | |
21 | * mballoc.c contains the multiblocks allocation routines | |
22 | */ | |
23 | ||
24 | #include <linux/time.h> | |
25 | #include <linux/fs.h> | |
26 | #include <linux/namei.h> | |
27 | #include <linux/ext4_jbd2.h> | |
28 | #include <linux/ext4_fs.h> | |
29 | #include <linux/quotaops.h> | |
30 | #include <linux/buffer_head.h> | |
31 | #include <linux/module.h> | |
32 | #include <linux/swap.h> | |
33 | #include <linux/proc_fs.h> | |
34 | #include <linux/pagemap.h> | |
35 | #include <linux/seq_file.h> | |
36 | #include <linux/version.h> | |
37 | #include "group.h" | |
38 | ||
39 | /* | |
40 | * MUSTDO: | |
41 | * - test ext4_ext_search_left() and ext4_ext_search_right() | |
42 | * - search for metadata in few groups | |
43 | * | |
44 | * TODO v4: | |
45 | * - normalization should take into account whether file is still open | |
46 | * - discard preallocations if no free space left (policy?) | |
47 | * - don't normalize tails | |
48 | * - quota | |
49 | * - reservation for superuser | |
50 | * | |
51 | * TODO v3: | |
52 | * - bitmap read-ahead (proposed by Oleg Drokin aka green) | |
53 | * - track min/max extents in each group for better group selection | |
54 | * - mb_mark_used() may allocate chunk right after splitting buddy | |
55 | * - tree of groups sorted by number of free blocks | |
56 | * - error handling | |
57 | */ | |
58 | ||
59 | /* | |
60 | * The allocation request involve request for multiple number of blocks | |
61 | * near to the goal(block) value specified. | |
62 | * | |
63 | * During initialization phase of the allocator we decide to use the group | |
64 | * preallocation or inode preallocation depending on the size file. The | |
65 | * size of the file could be the resulting file size we would have after | |
66 | * allocation or the current file size which ever is larger. If the size is | |
67 | * less that sbi->s_mb_stream_request we select the group | |
68 | * preallocation. The default value of s_mb_stream_request is 16 | |
69 | * blocks. This can also be tuned via | |
70 | * /proc/fs/ext4/<partition>/stream_req. The value is represented in terms | |
71 | * of number of blocks. | |
72 | * | |
73 | * The main motivation for having small file use group preallocation is to | |
74 | * ensure that we have small file closer in the disk. | |
75 | * | |
76 | * First stage the allocator looks at the inode prealloc list | |
77 | * ext4_inode_info->i_prealloc_list contain list of prealloc spaces for | |
78 | * this particular inode. The inode prealloc space is represented as: | |
79 | * | |
80 | * pa_lstart -> the logical start block for this prealloc space | |
81 | * pa_pstart -> the physical start block for this prealloc space | |
82 | * pa_len -> lenght for this prealloc space | |
83 | * pa_free -> free space available in this prealloc space | |
84 | * | |
85 | * The inode preallocation space is used looking at the _logical_ start | |
86 | * block. If only the logical file block falls within the range of prealloc | |
87 | * space we will consume the particular prealloc space. This make sure that | |
88 | * that the we have contiguous physical blocks representing the file blocks | |
89 | * | |
90 | * The important thing to be noted in case of inode prealloc space is that | |
91 | * we don't modify the values associated to inode prealloc space except | |
92 | * pa_free. | |
93 | * | |
94 | * If we are not able to find blocks in the inode prealloc space and if we | |
95 | * have the group allocation flag set then we look at the locality group | |
96 | * prealloc space. These are per CPU prealloc list repreasented as | |
97 | * | |
98 | * ext4_sb_info.s_locality_groups[smp_processor_id()] | |
99 | * | |
100 | * The reason for having a per cpu locality group is to reduce the contention | |
101 | * between CPUs. It is possible to get scheduled at this point. | |
102 | * | |
103 | * The locality group prealloc space is used looking at whether we have | |
104 | * enough free space (pa_free) withing the prealloc space. | |
105 | * | |
106 | * If we can't allocate blocks via inode prealloc or/and locality group | |
107 | * prealloc then we look at the buddy cache. The buddy cache is represented | |
108 | * by ext4_sb_info.s_buddy_cache (struct inode) whose file offset gets | |
109 | * mapped to the buddy and bitmap information regarding different | |
110 | * groups. The buddy information is attached to buddy cache inode so that | |
111 | * we can access them through the page cache. The information regarding | |
112 | * each group is loaded via ext4_mb_load_buddy. The information involve | |
113 | * block bitmap and buddy information. The information are stored in the | |
114 | * inode as: | |
115 | * | |
116 | * { page } | |
117 | * [ group 0 buddy][ group 0 bitmap] [group 1][ group 1]... | |
118 | * | |
119 | * | |
120 | * one block each for bitmap and buddy information. So for each group we | |
121 | * take up 2 blocks. A page can contain blocks_per_page (PAGE_CACHE_SIZE / | |
122 | * blocksize) blocks. So it can have information regarding groups_per_page | |
123 | * which is blocks_per_page/2 | |
124 | * | |
125 | * The buddy cache inode is not stored on disk. The inode is thrown | |
126 | * away when the filesystem is unmounted. | |
127 | * | |
128 | * We look for count number of blocks in the buddy cache. If we were able | |
129 | * to locate that many free blocks we return with additional information | |
130 | * regarding rest of the contiguous physical block available | |
131 | * | |
132 | * Before allocating blocks via buddy cache we normalize the request | |
133 | * blocks. This ensure we ask for more blocks that we needed. The extra | |
134 | * blocks that we get after allocation is added to the respective prealloc | |
135 | * list. In case of inode preallocation we follow a list of heuristics | |
136 | * based on file size. This can be found in ext4_mb_normalize_request. If | |
137 | * we are doing a group prealloc we try to normalize the request to | |
138 | * sbi->s_mb_group_prealloc. Default value of s_mb_group_prealloc is set to | |
139 | * 512 blocks. This can be tuned via | |
140 | * /proc/fs/ext4/<partition/group_prealloc. The value is represented in | |
141 | * terms of number of blocks. If we have mounted the file system with -O | |
142 | * stripe=<value> option the group prealloc request is normalized to the | |
143 | * stripe value (sbi->s_stripe) | |
144 | * | |
145 | * The regular allocator(using the buddy cache) support few tunables. | |
146 | * | |
147 | * /proc/fs/ext4/<partition>/min_to_scan | |
148 | * /proc/fs/ext4/<partition>/max_to_scan | |
149 | * /proc/fs/ext4/<partition>/order2_req | |
150 | * | |
151 | * The regular allocator use buddy scan only if the request len is power of | |
152 | * 2 blocks and the order of allocation is >= sbi->s_mb_order2_reqs. The | |
153 | * value of s_mb_order2_reqs can be tuned via | |
154 | * /proc/fs/ext4/<partition>/order2_req. If the request len is equal to | |
155 | * stripe size (sbi->s_stripe), we try to search for contigous block in | |
156 | * stripe size. This should result in better allocation on RAID setup. If | |
157 | * not we search in the specific group using bitmap for best extents. The | |
158 | * tunable min_to_scan and max_to_scan controll the behaviour here. | |
159 | * min_to_scan indicate how long the mballoc __must__ look for a best | |
160 | * extent and max_to_scanindicate how long the mballoc __can__ look for a | |
161 | * best extent in the found extents. Searching for the blocks starts with | |
162 | * the group specified as the goal value in allocation context via | |
163 | * ac_g_ex. Each group is first checked based on the criteria whether it | |
164 | * can used for allocation. ext4_mb_good_group explains how the groups are | |
165 | * checked. | |
166 | * | |
167 | * Both the prealloc space are getting populated as above. So for the first | |
168 | * request we will hit the buddy cache which will result in this prealloc | |
169 | * space getting filled. The prealloc space is then later used for the | |
170 | * subsequent request. | |
171 | */ | |
172 | ||
173 | /* | |
174 | * mballoc operates on the following data: | |
175 | * - on-disk bitmap | |
176 | * - in-core buddy (actually includes buddy and bitmap) | |
177 | * - preallocation descriptors (PAs) | |
178 | * | |
179 | * there are two types of preallocations: | |
180 | * - inode | |
181 | * assiged to specific inode and can be used for this inode only. | |
182 | * it describes part of inode's space preallocated to specific | |
183 | * physical blocks. any block from that preallocated can be used | |
184 | * independent. the descriptor just tracks number of blocks left | |
185 | * unused. so, before taking some block from descriptor, one must | |
186 | * make sure corresponded logical block isn't allocated yet. this | |
187 | * also means that freeing any block within descriptor's range | |
188 | * must discard all preallocated blocks. | |
189 | * - locality group | |
190 | * assigned to specific locality group which does not translate to | |
191 | * permanent set of inodes: inode can join and leave group. space | |
192 | * from this type of preallocation can be used for any inode. thus | |
193 | * it's consumed from the beginning to the end. | |
194 | * | |
195 | * relation between them can be expressed as: | |
196 | * in-core buddy = on-disk bitmap + preallocation descriptors | |
197 | * | |
198 | * this mean blocks mballoc considers used are: | |
199 | * - allocated blocks (persistent) | |
200 | * - preallocated blocks (non-persistent) | |
201 | * | |
202 | * consistency in mballoc world means that at any time a block is either | |
203 | * free or used in ALL structures. notice: "any time" should not be read | |
204 | * literally -- time is discrete and delimited by locks. | |
205 | * | |
206 | * to keep it simple, we don't use block numbers, instead we count number of | |
207 | * blocks: how many blocks marked used/free in on-disk bitmap, buddy and PA. | |
208 | * | |
209 | * all operations can be expressed as: | |
210 | * - init buddy: buddy = on-disk + PAs | |
211 | * - new PA: buddy += N; PA = N | |
212 | * - use inode PA: on-disk += N; PA -= N | |
213 | * - discard inode PA buddy -= on-disk - PA; PA = 0 | |
214 | * - use locality group PA on-disk += N; PA -= N | |
215 | * - discard locality group PA buddy -= PA; PA = 0 | |
216 | * note: 'buddy -= on-disk - PA' is used to show that on-disk bitmap | |
217 | * is used in real operation because we can't know actual used | |
218 | * bits from PA, only from on-disk bitmap | |
219 | * | |
220 | * if we follow this strict logic, then all operations above should be atomic. | |
221 | * given some of them can block, we'd have to use something like semaphores | |
222 | * killing performance on high-end SMP hardware. let's try to relax it using | |
223 | * the following knowledge: | |
224 | * 1) if buddy is referenced, it's already initialized | |
225 | * 2) while block is used in buddy and the buddy is referenced, | |
226 | * nobody can re-allocate that block | |
227 | * 3) we work on bitmaps and '+' actually means 'set bits'. if on-disk has | |
228 | * bit set and PA claims same block, it's OK. IOW, one can set bit in | |
229 | * on-disk bitmap if buddy has same bit set or/and PA covers corresponded | |
230 | * block | |
231 | * | |
232 | * so, now we're building a concurrency table: | |
233 | * - init buddy vs. | |
234 | * - new PA | |
235 | * blocks for PA are allocated in the buddy, buddy must be referenced | |
236 | * until PA is linked to allocation group to avoid concurrent buddy init | |
237 | * - use inode PA | |
238 | * we need to make sure that either on-disk bitmap or PA has uptodate data | |
239 | * given (3) we care that PA-=N operation doesn't interfere with init | |
240 | * - discard inode PA | |
241 | * the simplest way would be to have buddy initialized by the discard | |
242 | * - use locality group PA | |
243 | * again PA-=N must be serialized with init | |
244 | * - discard locality group PA | |
245 | * the simplest way would be to have buddy initialized by the discard | |
246 | * - new PA vs. | |
247 | * - use inode PA | |
248 | * i_data_sem serializes them | |
249 | * - discard inode PA | |
250 | * discard process must wait until PA isn't used by another process | |
251 | * - use locality group PA | |
252 | * some mutex should serialize them | |
253 | * - discard locality group PA | |
254 | * discard process must wait until PA isn't used by another process | |
255 | * - use inode PA | |
256 | * - use inode PA | |
257 | * i_data_sem or another mutex should serializes them | |
258 | * - discard inode PA | |
259 | * discard process must wait until PA isn't used by another process | |
260 | * - use locality group PA | |
261 | * nothing wrong here -- they're different PAs covering different blocks | |
262 | * - discard locality group PA | |
263 | * discard process must wait until PA isn't used by another process | |
264 | * | |
265 | * now we're ready to make few consequences: | |
266 | * - PA is referenced and while it is no discard is possible | |
267 | * - PA is referenced until block isn't marked in on-disk bitmap | |
268 | * - PA changes only after on-disk bitmap | |
269 | * - discard must not compete with init. either init is done before | |
270 | * any discard or they're serialized somehow | |
271 | * - buddy init as sum of on-disk bitmap and PAs is done atomically | |
272 | * | |
273 | * a special case when we've used PA to emptiness. no need to modify buddy | |
274 | * in this case, but we should care about concurrent init | |
275 | * | |
276 | */ | |
277 | ||
278 | /* | |
279 | * Logic in few words: | |
280 | * | |
281 | * - allocation: | |
282 | * load group | |
283 | * find blocks | |
284 | * mark bits in on-disk bitmap | |
285 | * release group | |
286 | * | |
287 | * - use preallocation: | |
288 | * find proper PA (per-inode or group) | |
289 | * load group | |
290 | * mark bits in on-disk bitmap | |
291 | * release group | |
292 | * release PA | |
293 | * | |
294 | * - free: | |
295 | * load group | |
296 | * mark bits in on-disk bitmap | |
297 | * release group | |
298 | * | |
299 | * - discard preallocations in group: | |
300 | * mark PAs deleted | |
301 | * move them onto local list | |
302 | * load on-disk bitmap | |
303 | * load group | |
304 | * remove PA from object (inode or locality group) | |
305 | * mark free blocks in-core | |
306 | * | |
307 | * - discard inode's preallocations: | |
308 | */ | |
309 | ||
310 | /* | |
311 | * Locking rules | |
312 | * | |
313 | * Locks: | |
314 | * - bitlock on a group (group) | |
315 | * - object (inode/locality) (object) | |
316 | * - per-pa lock (pa) | |
317 | * | |
318 | * Paths: | |
319 | * - new pa | |
320 | * object | |
321 | * group | |
322 | * | |
323 | * - find and use pa: | |
324 | * pa | |
325 | * | |
326 | * - release consumed pa: | |
327 | * pa | |
328 | * group | |
329 | * object | |
330 | * | |
331 | * - generate in-core bitmap: | |
332 | * group | |
333 | * pa | |
334 | * | |
335 | * - discard all for given object (inode, locality group): | |
336 | * object | |
337 | * pa | |
338 | * group | |
339 | * | |
340 | * - discard all for given group: | |
341 | * group | |
342 | * pa | |
343 | * group | |
344 | * object | |
345 | * | |
346 | */ | |
347 | ||
348 | /* | |
349 | * with AGGRESSIVE_CHECK allocator runs consistency checks over | |
350 | * structures. these checks slow things down a lot | |
351 | */ | |
352 | #define AGGRESSIVE_CHECK__ | |
353 | ||
354 | /* | |
355 | * with DOUBLE_CHECK defined mballoc creates persistent in-core | |
356 | * bitmaps, maintains and uses them to check for double allocations | |
357 | */ | |
358 | #define DOUBLE_CHECK__ | |
359 | ||
360 | /* | |
361 | */ | |
362 | #define MB_DEBUG__ | |
363 | #ifdef MB_DEBUG | |
364 | #define mb_debug(fmt, a...) printk(fmt, ##a) | |
365 | #else | |
366 | #define mb_debug(fmt, a...) | |
367 | #endif | |
368 | ||
369 | /* | |
370 | * with EXT4_MB_HISTORY mballoc stores last N allocations in memory | |
371 | * and you can monitor it in /proc/fs/ext4/<dev>/mb_history | |
372 | */ | |
373 | #define EXT4_MB_HISTORY | |
374 | #define EXT4_MB_HISTORY_ALLOC 1 /* allocation */ | |
375 | #define EXT4_MB_HISTORY_PREALLOC 2 /* preallocated blocks used */ | |
376 | #define EXT4_MB_HISTORY_DISCARD 4 /* preallocation discarded */ | |
377 | #define EXT4_MB_HISTORY_FREE 8 /* free */ | |
378 | ||
379 | #define EXT4_MB_HISTORY_DEFAULT (EXT4_MB_HISTORY_ALLOC | \ | |
380 | EXT4_MB_HISTORY_PREALLOC) | |
381 | ||
382 | /* | |
383 | * How long mballoc can look for a best extent (in found extents) | |
384 | */ | |
385 | #define MB_DEFAULT_MAX_TO_SCAN 200 | |
386 | ||
387 | /* | |
388 | * How long mballoc must look for a best extent | |
389 | */ | |
390 | #define MB_DEFAULT_MIN_TO_SCAN 10 | |
391 | ||
392 | /* | |
393 | * How many groups mballoc will scan looking for the best chunk | |
394 | */ | |
395 | #define MB_DEFAULT_MAX_GROUPS_TO_SCAN 5 | |
396 | ||
397 | /* | |
398 | * with 'ext4_mb_stats' allocator will collect stats that will be | |
399 | * shown at umount. The collecting costs though! | |
400 | */ | |
401 | #define MB_DEFAULT_STATS 1 | |
402 | ||
403 | /* | |
404 | * files smaller than MB_DEFAULT_STREAM_THRESHOLD are served | |
405 | * by the stream allocator, which purpose is to pack requests | |
406 | * as close each to other as possible to produce smooth I/O traffic | |
407 | * We use locality group prealloc space for stream request. | |
408 | * We can tune the same via /proc/fs/ext4/<parition>/stream_req | |
409 | */ | |
410 | #define MB_DEFAULT_STREAM_THRESHOLD 16 /* 64K */ | |
411 | ||
412 | /* | |
413 | * for which requests use 2^N search using buddies | |
414 | */ | |
415 | #define MB_DEFAULT_ORDER2_REQS 2 | |
416 | ||
417 | /* | |
418 | * default group prealloc size 512 blocks | |
419 | */ | |
420 | #define MB_DEFAULT_GROUP_PREALLOC 512 | |
421 | ||
422 | static struct kmem_cache *ext4_pspace_cachep; | |
256bdb49 | 423 | static struct kmem_cache *ext4_ac_cachep; |
c9de560d AT |
424 | |
425 | #ifdef EXT4_BB_MAX_BLOCKS | |
426 | #undef EXT4_BB_MAX_BLOCKS | |
427 | #endif | |
428 | #define EXT4_BB_MAX_BLOCKS 30 | |
429 | ||
430 | struct ext4_free_metadata { | |
431 | ext4_group_t group; | |
432 | unsigned short num; | |
433 | ext4_grpblk_t blocks[EXT4_BB_MAX_BLOCKS]; | |
434 | struct list_head list; | |
435 | }; | |
436 | ||
437 | struct ext4_group_info { | |
438 | unsigned long bb_state; | |
439 | unsigned long bb_tid; | |
440 | struct ext4_free_metadata *bb_md_cur; | |
441 | unsigned short bb_first_free; | |
442 | unsigned short bb_free; | |
443 | unsigned short bb_fragments; | |
444 | struct list_head bb_prealloc_list; | |
445 | #ifdef DOUBLE_CHECK | |
446 | void *bb_bitmap; | |
447 | #endif | |
448 | unsigned short bb_counters[]; | |
449 | }; | |
450 | ||
451 | #define EXT4_GROUP_INFO_NEED_INIT_BIT 0 | |
452 | #define EXT4_GROUP_INFO_LOCKED_BIT 1 | |
453 | ||
454 | #define EXT4_MB_GRP_NEED_INIT(grp) \ | |
455 | (test_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &((grp)->bb_state))) | |
456 | ||
457 | ||
458 | struct ext4_prealloc_space { | |
459 | struct list_head pa_inode_list; | |
460 | struct list_head pa_group_list; | |
461 | union { | |
462 | struct list_head pa_tmp_list; | |
463 | struct rcu_head pa_rcu; | |
464 | } u; | |
465 | spinlock_t pa_lock; | |
466 | atomic_t pa_count; | |
467 | unsigned pa_deleted; | |
468 | ext4_fsblk_t pa_pstart; /* phys. block */ | |
469 | ext4_lblk_t pa_lstart; /* log. block */ | |
470 | unsigned short pa_len; /* len of preallocated chunk */ | |
471 | unsigned short pa_free; /* how many blocks are free */ | |
472 | unsigned short pa_linear; /* consumed in one direction | |
473 | * strictly, for grp prealloc */ | |
474 | spinlock_t *pa_obj_lock; | |
475 | struct inode *pa_inode; /* hack, for history only */ | |
476 | }; | |
477 | ||
478 | ||
479 | struct ext4_free_extent { | |
480 | ext4_lblk_t fe_logical; | |
481 | ext4_grpblk_t fe_start; | |
482 | ext4_group_t fe_group; | |
483 | int fe_len; | |
484 | }; | |
485 | ||
486 | /* | |
487 | * Locality group: | |
488 | * we try to group all related changes together | |
489 | * so that writeback can flush/allocate them together as well | |
490 | */ | |
491 | struct ext4_locality_group { | |
492 | /* for allocator */ | |
493 | struct mutex lg_mutex; /* to serialize allocates */ | |
494 | struct list_head lg_prealloc_list;/* list of preallocations */ | |
495 | spinlock_t lg_prealloc_lock; | |
496 | }; | |
497 | ||
498 | struct ext4_allocation_context { | |
499 | struct inode *ac_inode; | |
500 | struct super_block *ac_sb; | |
501 | ||
502 | /* original request */ | |
503 | struct ext4_free_extent ac_o_ex; | |
504 | ||
505 | /* goal request (after normalization) */ | |
506 | struct ext4_free_extent ac_g_ex; | |
507 | ||
508 | /* the best found extent */ | |
509 | struct ext4_free_extent ac_b_ex; | |
510 | ||
511 | /* copy of the bext found extent taken before preallocation efforts */ | |
512 | struct ext4_free_extent ac_f_ex; | |
513 | ||
514 | /* number of iterations done. we have to track to limit searching */ | |
515 | unsigned long ac_ex_scanned; | |
516 | __u16 ac_groups_scanned; | |
517 | __u16 ac_found; | |
518 | __u16 ac_tail; | |
519 | __u16 ac_buddy; | |
520 | __u16 ac_flags; /* allocation hints */ | |
521 | __u8 ac_status; | |
522 | __u8 ac_criteria; | |
523 | __u8 ac_repeats; | |
524 | __u8 ac_2order; /* if request is to allocate 2^N blocks and | |
525 | * N > 0, the field stores N, otherwise 0 */ | |
526 | __u8 ac_op; /* operation, for history only */ | |
527 | struct page *ac_bitmap_page; | |
528 | struct page *ac_buddy_page; | |
529 | struct ext4_prealloc_space *ac_pa; | |
530 | struct ext4_locality_group *ac_lg; | |
531 | }; | |
532 | ||
533 | #define AC_STATUS_CONTINUE 1 | |
534 | #define AC_STATUS_FOUND 2 | |
535 | #define AC_STATUS_BREAK 3 | |
536 | ||
537 | struct ext4_mb_history { | |
538 | struct ext4_free_extent orig; /* orig allocation */ | |
539 | struct ext4_free_extent goal; /* goal allocation */ | |
540 | struct ext4_free_extent result; /* result allocation */ | |
541 | unsigned pid; | |
542 | unsigned ino; | |
543 | __u16 found; /* how many extents have been found */ | |
544 | __u16 groups; /* how many groups have been scanned */ | |
545 | __u16 tail; /* what tail broke some buddy */ | |
546 | __u16 buddy; /* buddy the tail ^^^ broke */ | |
547 | __u16 flags; | |
548 | __u8 cr:3; /* which phase the result extent was found at */ | |
549 | __u8 op:4; | |
550 | __u8 merged:1; | |
551 | }; | |
552 | ||
553 | struct ext4_buddy { | |
554 | struct page *bd_buddy_page; | |
555 | void *bd_buddy; | |
556 | struct page *bd_bitmap_page; | |
557 | void *bd_bitmap; | |
558 | struct ext4_group_info *bd_info; | |
559 | struct super_block *bd_sb; | |
560 | __u16 bd_blkbits; | |
561 | ext4_group_t bd_group; | |
562 | }; | |
563 | #define EXT4_MB_BITMAP(e4b) ((e4b)->bd_bitmap) | |
564 | #define EXT4_MB_BUDDY(e4b) ((e4b)->bd_buddy) | |
565 | ||
566 | #ifndef EXT4_MB_HISTORY | |
567 | static inline void ext4_mb_store_history(struct ext4_allocation_context *ac) | |
568 | { | |
569 | return; | |
570 | } | |
571 | #else | |
572 | static void ext4_mb_store_history(struct ext4_allocation_context *ac); | |
573 | #endif | |
574 | ||
575 | #define in_range(b, first, len) ((b) >= (first) && (b) <= (first) + (len) - 1) | |
576 | ||
577 | static struct proc_dir_entry *proc_root_ext4; | |
578 | struct buffer_head *read_block_bitmap(struct super_block *, ext4_group_t); | |
579 | ext4_fsblk_t ext4_new_blocks_old(handle_t *handle, struct inode *inode, | |
580 | ext4_fsblk_t goal, unsigned long *count, int *errp); | |
581 | ||
582 | static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap, | |
583 | ext4_group_t group); | |
584 | static void ext4_mb_poll_new_transaction(struct super_block *, handle_t *); | |
585 | static void ext4_mb_free_committed_blocks(struct super_block *); | |
586 | static void ext4_mb_return_to_preallocation(struct inode *inode, | |
587 | struct ext4_buddy *e4b, sector_t block, | |
588 | int count); | |
589 | static void ext4_mb_put_pa(struct ext4_allocation_context *, | |
590 | struct super_block *, struct ext4_prealloc_space *pa); | |
591 | static int ext4_mb_init_per_dev_proc(struct super_block *sb); | |
592 | static int ext4_mb_destroy_per_dev_proc(struct super_block *sb); | |
593 | ||
594 | ||
595 | static inline void ext4_lock_group(struct super_block *sb, ext4_group_t group) | |
596 | { | |
597 | struct ext4_group_info *grinfo = ext4_get_group_info(sb, group); | |
598 | ||
599 | bit_spin_lock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state)); | |
600 | } | |
601 | ||
602 | static inline void ext4_unlock_group(struct super_block *sb, | |
603 | ext4_group_t group) | |
604 | { | |
605 | struct ext4_group_info *grinfo = ext4_get_group_info(sb, group); | |
606 | ||
607 | bit_spin_unlock(EXT4_GROUP_INFO_LOCKED_BIT, &(grinfo->bb_state)); | |
608 | } | |
609 | ||
610 | static inline int ext4_is_group_locked(struct super_block *sb, | |
611 | ext4_group_t group) | |
612 | { | |
613 | struct ext4_group_info *grinfo = ext4_get_group_info(sb, group); | |
614 | ||
615 | return bit_spin_is_locked(EXT4_GROUP_INFO_LOCKED_BIT, | |
616 | &(grinfo->bb_state)); | |
617 | } | |
618 | ||
619 | static ext4_fsblk_t ext4_grp_offs_to_block(struct super_block *sb, | |
620 | struct ext4_free_extent *fex) | |
621 | { | |
622 | ext4_fsblk_t block; | |
623 | ||
624 | block = (ext4_fsblk_t) fex->fe_group * EXT4_BLOCKS_PER_GROUP(sb) | |
625 | + fex->fe_start | |
626 | + le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); | |
627 | return block; | |
628 | } | |
629 | ||
630 | #if BITS_PER_LONG == 64 | |
631 | #define mb_correct_addr_and_bit(bit, addr) \ | |
632 | { \ | |
633 | bit += ((unsigned long) addr & 7UL) << 3; \ | |
634 | addr = (void *) ((unsigned long) addr & ~7UL); \ | |
635 | } | |
636 | #elif BITS_PER_LONG == 32 | |
637 | #define mb_correct_addr_and_bit(bit, addr) \ | |
638 | { \ | |
639 | bit += ((unsigned long) addr & 3UL) << 3; \ | |
640 | addr = (void *) ((unsigned long) addr & ~3UL); \ | |
641 | } | |
642 | #else | |
643 | #error "how many bits you are?!" | |
644 | #endif | |
645 | ||
646 | static inline int mb_test_bit(int bit, void *addr) | |
647 | { | |
648 | /* | |
649 | * ext4_test_bit on architecture like powerpc | |
650 | * needs unsigned long aligned address | |
651 | */ | |
652 | mb_correct_addr_and_bit(bit, addr); | |
653 | return ext4_test_bit(bit, addr); | |
654 | } | |
655 | ||
656 | static inline void mb_set_bit(int bit, void *addr) | |
657 | { | |
658 | mb_correct_addr_and_bit(bit, addr); | |
659 | ext4_set_bit(bit, addr); | |
660 | } | |
661 | ||
662 | static inline void mb_set_bit_atomic(spinlock_t *lock, int bit, void *addr) | |
663 | { | |
664 | mb_correct_addr_and_bit(bit, addr); | |
665 | ext4_set_bit_atomic(lock, bit, addr); | |
666 | } | |
667 | ||
668 | static inline void mb_clear_bit(int bit, void *addr) | |
669 | { | |
670 | mb_correct_addr_and_bit(bit, addr); | |
671 | ext4_clear_bit(bit, addr); | |
672 | } | |
673 | ||
674 | static inline void mb_clear_bit_atomic(spinlock_t *lock, int bit, void *addr) | |
675 | { | |
676 | mb_correct_addr_and_bit(bit, addr); | |
677 | ext4_clear_bit_atomic(lock, bit, addr); | |
678 | } | |
679 | ||
680 | static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max) | |
681 | { | |
682 | char *bb; | |
683 | ||
c9de560d AT |
684 | BUG_ON(EXT4_MB_BITMAP(e4b) == EXT4_MB_BUDDY(e4b)); |
685 | BUG_ON(max == NULL); | |
686 | ||
687 | if (order > e4b->bd_blkbits + 1) { | |
688 | *max = 0; | |
689 | return NULL; | |
690 | } | |
691 | ||
692 | /* at order 0 we see each particular block */ | |
693 | *max = 1 << (e4b->bd_blkbits + 3); | |
694 | if (order == 0) | |
695 | return EXT4_MB_BITMAP(e4b); | |
696 | ||
697 | bb = EXT4_MB_BUDDY(e4b) + EXT4_SB(e4b->bd_sb)->s_mb_offsets[order]; | |
698 | *max = EXT4_SB(e4b->bd_sb)->s_mb_maxs[order]; | |
699 | ||
700 | return bb; | |
701 | } | |
702 | ||
703 | #ifdef DOUBLE_CHECK | |
704 | static void mb_free_blocks_double(struct inode *inode, struct ext4_buddy *e4b, | |
705 | int first, int count) | |
706 | { | |
707 | int i; | |
708 | struct super_block *sb = e4b->bd_sb; | |
709 | ||
710 | if (unlikely(e4b->bd_info->bb_bitmap == NULL)) | |
711 | return; | |
712 | BUG_ON(!ext4_is_group_locked(sb, e4b->bd_group)); | |
713 | for (i = 0; i < count; i++) { | |
714 | if (!mb_test_bit(first + i, e4b->bd_info->bb_bitmap)) { | |
715 | ext4_fsblk_t blocknr; | |
716 | blocknr = e4b->bd_group * EXT4_BLOCKS_PER_GROUP(sb); | |
717 | blocknr += first + i; | |
718 | blocknr += | |
719 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); | |
720 | ||
721 | ext4_error(sb, __FUNCTION__, "double-free of inode" | |
722 | " %lu's block %llu(bit %u in group %lu)\n", | |
723 | inode ? inode->i_ino : 0, blocknr, | |
724 | first + i, e4b->bd_group); | |
725 | } | |
726 | mb_clear_bit(first + i, e4b->bd_info->bb_bitmap); | |
727 | } | |
728 | } | |
729 | ||
730 | static void mb_mark_used_double(struct ext4_buddy *e4b, int first, int count) | |
731 | { | |
732 | int i; | |
733 | ||
734 | if (unlikely(e4b->bd_info->bb_bitmap == NULL)) | |
735 | return; | |
736 | BUG_ON(!ext4_is_group_locked(e4b->bd_sb, e4b->bd_group)); | |
737 | for (i = 0; i < count; i++) { | |
738 | BUG_ON(mb_test_bit(first + i, e4b->bd_info->bb_bitmap)); | |
739 | mb_set_bit(first + i, e4b->bd_info->bb_bitmap); | |
740 | } | |
741 | } | |
742 | ||
743 | static void mb_cmp_bitmaps(struct ext4_buddy *e4b, void *bitmap) | |
744 | { | |
745 | if (memcmp(e4b->bd_info->bb_bitmap, bitmap, e4b->bd_sb->s_blocksize)) { | |
746 | unsigned char *b1, *b2; | |
747 | int i; | |
748 | b1 = (unsigned char *) e4b->bd_info->bb_bitmap; | |
749 | b2 = (unsigned char *) bitmap; | |
750 | for (i = 0; i < e4b->bd_sb->s_blocksize; i++) { | |
751 | if (b1[i] != b2[i]) { | |
752 | printk("corruption in group %lu at byte %u(%u):" | |
753 | " %x in copy != %x on disk/prealloc\n", | |
754 | e4b->bd_group, i, i * 8, b1[i], b2[i]); | |
755 | BUG(); | |
756 | } | |
757 | } | |
758 | } | |
759 | } | |
760 | ||
761 | #else | |
762 | static inline void mb_free_blocks_double(struct inode *inode, | |
763 | struct ext4_buddy *e4b, int first, int count) | |
764 | { | |
765 | return; | |
766 | } | |
767 | static inline void mb_mark_used_double(struct ext4_buddy *e4b, | |
768 | int first, int count) | |
769 | { | |
770 | return; | |
771 | } | |
772 | static inline void mb_cmp_bitmaps(struct ext4_buddy *e4b, void *bitmap) | |
773 | { | |
774 | return; | |
775 | } | |
776 | #endif | |
777 | ||
778 | #ifdef AGGRESSIVE_CHECK | |
779 | ||
780 | #define MB_CHECK_ASSERT(assert) \ | |
781 | do { \ | |
782 | if (!(assert)) { \ | |
783 | printk(KERN_EMERG \ | |
784 | "Assertion failure in %s() at %s:%d: \"%s\"\n", \ | |
785 | function, file, line, # assert); \ | |
786 | BUG(); \ | |
787 | } \ | |
788 | } while (0) | |
789 | ||
790 | static int __mb_check_buddy(struct ext4_buddy *e4b, char *file, | |
791 | const char *function, int line) | |
792 | { | |
793 | struct super_block *sb = e4b->bd_sb; | |
794 | int order = e4b->bd_blkbits + 1; | |
795 | int max; | |
796 | int max2; | |
797 | int i; | |
798 | int j; | |
799 | int k; | |
800 | int count; | |
801 | struct ext4_group_info *grp; | |
802 | int fragments = 0; | |
803 | int fstart; | |
804 | struct list_head *cur; | |
805 | void *buddy; | |
806 | void *buddy2; | |
807 | ||
808 | if (!test_opt(sb, MBALLOC)) | |
809 | return 0; | |
810 | ||
811 | { | |
812 | static int mb_check_counter; | |
813 | if (mb_check_counter++ % 100 != 0) | |
814 | return 0; | |
815 | } | |
816 | ||
817 | while (order > 1) { | |
818 | buddy = mb_find_buddy(e4b, order, &max); | |
819 | MB_CHECK_ASSERT(buddy); | |
820 | buddy2 = mb_find_buddy(e4b, order - 1, &max2); | |
821 | MB_CHECK_ASSERT(buddy2); | |
822 | MB_CHECK_ASSERT(buddy != buddy2); | |
823 | MB_CHECK_ASSERT(max * 2 == max2); | |
824 | ||
825 | count = 0; | |
826 | for (i = 0; i < max; i++) { | |
827 | ||
828 | if (mb_test_bit(i, buddy)) { | |
829 | /* only single bit in buddy2 may be 1 */ | |
830 | if (!mb_test_bit(i << 1, buddy2)) { | |
831 | MB_CHECK_ASSERT( | |
832 | mb_test_bit((i<<1)+1, buddy2)); | |
833 | } else if (!mb_test_bit((i << 1) + 1, buddy2)) { | |
834 | MB_CHECK_ASSERT( | |
835 | mb_test_bit(i << 1, buddy2)); | |
836 | } | |
837 | continue; | |
838 | } | |
839 | ||
840 | /* both bits in buddy2 must be 0 */ | |
841 | MB_CHECK_ASSERT(mb_test_bit(i << 1, buddy2)); | |
842 | MB_CHECK_ASSERT(mb_test_bit((i << 1) + 1, buddy2)); | |
843 | ||
844 | for (j = 0; j < (1 << order); j++) { | |
845 | k = (i * (1 << order)) + j; | |
846 | MB_CHECK_ASSERT( | |
847 | !mb_test_bit(k, EXT4_MB_BITMAP(e4b))); | |
848 | } | |
849 | count++; | |
850 | } | |
851 | MB_CHECK_ASSERT(e4b->bd_info->bb_counters[order] == count); | |
852 | order--; | |
853 | } | |
854 | ||
855 | fstart = -1; | |
856 | buddy = mb_find_buddy(e4b, 0, &max); | |
857 | for (i = 0; i < max; i++) { | |
858 | if (!mb_test_bit(i, buddy)) { | |
859 | MB_CHECK_ASSERT(i >= e4b->bd_info->bb_first_free); | |
860 | if (fstart == -1) { | |
861 | fragments++; | |
862 | fstart = i; | |
863 | } | |
864 | continue; | |
865 | } | |
866 | fstart = -1; | |
867 | /* check used bits only */ | |
868 | for (j = 0; j < e4b->bd_blkbits + 1; j++) { | |
869 | buddy2 = mb_find_buddy(e4b, j, &max2); | |
870 | k = i >> j; | |
871 | MB_CHECK_ASSERT(k < max2); | |
872 | MB_CHECK_ASSERT(mb_test_bit(k, buddy2)); | |
873 | } | |
874 | } | |
875 | MB_CHECK_ASSERT(!EXT4_MB_GRP_NEED_INIT(e4b->bd_info)); | |
876 | MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments); | |
877 | ||
878 | grp = ext4_get_group_info(sb, e4b->bd_group); | |
879 | buddy = mb_find_buddy(e4b, 0, &max); | |
880 | list_for_each(cur, &grp->bb_prealloc_list) { | |
881 | ext4_group_t groupnr; | |
882 | struct ext4_prealloc_space *pa; | |
883 | pa = list_entry(cur, struct ext4_prealloc_space, group_list); | |
884 | ext4_get_group_no_and_offset(sb, pa->pstart, &groupnr, &k); | |
885 | MB_CHECK_ASSERT(groupnr == e4b->bd_group); | |
886 | for (i = 0; i < pa->len; i++) | |
887 | MB_CHECK_ASSERT(mb_test_bit(k + i, buddy)); | |
888 | } | |
889 | return 0; | |
890 | } | |
891 | #undef MB_CHECK_ASSERT | |
892 | #define mb_check_buddy(e4b) __mb_check_buddy(e4b, \ | |
893 | __FILE__, __FUNCTION__, __LINE__) | |
894 | #else | |
895 | #define mb_check_buddy(e4b) | |
896 | #endif | |
897 | ||
898 | /* FIXME!! need more doc */ | |
899 | static void ext4_mb_mark_free_simple(struct super_block *sb, | |
900 | void *buddy, unsigned first, int len, | |
901 | struct ext4_group_info *grp) | |
902 | { | |
903 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
904 | unsigned short min; | |
905 | unsigned short max; | |
906 | unsigned short chunk; | |
907 | unsigned short border; | |
908 | ||
909 | BUG_ON(len >= EXT4_BLOCKS_PER_GROUP(sb)); | |
910 | ||
911 | border = 2 << sb->s_blocksize_bits; | |
912 | ||
913 | while (len > 0) { | |
914 | /* find how many blocks can be covered since this position */ | |
915 | max = ffs(first | border) - 1; | |
916 | ||
917 | /* find how many blocks of power 2 we need to mark */ | |
918 | min = fls(len) - 1; | |
919 | ||
920 | if (max < min) | |
921 | min = max; | |
922 | chunk = 1 << min; | |
923 | ||
924 | /* mark multiblock chunks only */ | |
925 | grp->bb_counters[min]++; | |
926 | if (min > 0) | |
927 | mb_clear_bit(first >> min, | |
928 | buddy + sbi->s_mb_offsets[min]); | |
929 | ||
930 | len -= chunk; | |
931 | first += chunk; | |
932 | } | |
933 | } | |
934 | ||
935 | static void ext4_mb_generate_buddy(struct super_block *sb, | |
936 | void *buddy, void *bitmap, ext4_group_t group) | |
937 | { | |
938 | struct ext4_group_info *grp = ext4_get_group_info(sb, group); | |
939 | unsigned short max = EXT4_BLOCKS_PER_GROUP(sb); | |
940 | unsigned short i = 0; | |
941 | unsigned short first; | |
942 | unsigned short len; | |
943 | unsigned free = 0; | |
944 | unsigned fragments = 0; | |
945 | unsigned long long period = get_cycles(); | |
946 | ||
947 | /* initialize buddy from bitmap which is aggregation | |
948 | * of on-disk bitmap and preallocations */ | |
949 | i = ext4_find_next_zero_bit(bitmap, max, 0); | |
950 | grp->bb_first_free = i; | |
951 | while (i < max) { | |
952 | fragments++; | |
953 | first = i; | |
954 | i = ext4_find_next_bit(bitmap, max, i); | |
955 | len = i - first; | |
956 | free += len; | |
957 | if (len > 1) | |
958 | ext4_mb_mark_free_simple(sb, buddy, first, len, grp); | |
959 | else | |
960 | grp->bb_counters[0]++; | |
961 | if (i < max) | |
962 | i = ext4_find_next_zero_bit(bitmap, max, i); | |
963 | } | |
964 | grp->bb_fragments = fragments; | |
965 | ||
966 | if (free != grp->bb_free) { | |
26346ff6 | 967 | ext4_error(sb, __FUNCTION__, |
c9de560d AT |
968 | "EXT4-fs: group %lu: %u blocks in bitmap, %u in gd\n", |
969 | group, free, grp->bb_free); | |
970 | grp->bb_free = free; | |
971 | } | |
972 | ||
973 | clear_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, &(grp->bb_state)); | |
974 | ||
975 | period = get_cycles() - period; | |
976 | spin_lock(&EXT4_SB(sb)->s_bal_lock); | |
977 | EXT4_SB(sb)->s_mb_buddies_generated++; | |
978 | EXT4_SB(sb)->s_mb_generation_time += period; | |
979 | spin_unlock(&EXT4_SB(sb)->s_bal_lock); | |
980 | } | |
981 | ||
982 | /* The buddy information is attached the buddy cache inode | |
983 | * for convenience. The information regarding each group | |
984 | * is loaded via ext4_mb_load_buddy. The information involve | |
985 | * block bitmap and buddy information. The information are | |
986 | * stored in the inode as | |
987 | * | |
988 | * { page } | |
989 | * [ group 0 buddy][ group 0 bitmap] [group 1][ group 1]... | |
990 | * | |
991 | * | |
992 | * one block each for bitmap and buddy information. | |
993 | * So for each group we take up 2 blocks. A page can | |
994 | * contain blocks_per_page (PAGE_CACHE_SIZE / blocksize) blocks. | |
995 | * So it can have information regarding groups_per_page which | |
996 | * is blocks_per_page/2 | |
997 | */ | |
998 | ||
999 | static int ext4_mb_init_cache(struct page *page, char *incore) | |
1000 | { | |
1001 | int blocksize; | |
1002 | int blocks_per_page; | |
1003 | int groups_per_page; | |
1004 | int err = 0; | |
1005 | int i; | |
1006 | ext4_group_t first_group; | |
1007 | int first_block; | |
1008 | struct super_block *sb; | |
1009 | struct buffer_head *bhs; | |
1010 | struct buffer_head **bh; | |
1011 | struct inode *inode; | |
1012 | char *data; | |
1013 | char *bitmap; | |
1014 | ||
1015 | mb_debug("init page %lu\n", page->index); | |
1016 | ||
1017 | inode = page->mapping->host; | |
1018 | sb = inode->i_sb; | |
1019 | blocksize = 1 << inode->i_blkbits; | |
1020 | blocks_per_page = PAGE_CACHE_SIZE / blocksize; | |
1021 | ||
1022 | groups_per_page = blocks_per_page >> 1; | |
1023 | if (groups_per_page == 0) | |
1024 | groups_per_page = 1; | |
1025 | ||
1026 | /* allocate buffer_heads to read bitmaps */ | |
1027 | if (groups_per_page > 1) { | |
1028 | err = -ENOMEM; | |
1029 | i = sizeof(struct buffer_head *) * groups_per_page; | |
1030 | bh = kzalloc(i, GFP_NOFS); | |
1031 | if (bh == NULL) | |
1032 | goto out; | |
1033 | } else | |
1034 | bh = &bhs; | |
1035 | ||
1036 | first_group = page->index * blocks_per_page / 2; | |
1037 | ||
1038 | /* read all groups the page covers into the cache */ | |
1039 | for (i = 0; i < groups_per_page; i++) { | |
1040 | struct ext4_group_desc *desc; | |
1041 | ||
1042 | if (first_group + i >= EXT4_SB(sb)->s_groups_count) | |
1043 | break; | |
1044 | ||
1045 | err = -EIO; | |
1046 | desc = ext4_get_group_desc(sb, first_group + i, NULL); | |
1047 | if (desc == NULL) | |
1048 | goto out; | |
1049 | ||
1050 | err = -ENOMEM; | |
1051 | bh[i] = sb_getblk(sb, ext4_block_bitmap(sb, desc)); | |
1052 | if (bh[i] == NULL) | |
1053 | goto out; | |
1054 | ||
1055 | if (bh_uptodate_or_lock(bh[i])) | |
1056 | continue; | |
1057 | ||
1058 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { | |
1059 | ext4_init_block_bitmap(sb, bh[i], | |
1060 | first_group + i, desc); | |
1061 | set_buffer_uptodate(bh[i]); | |
1062 | unlock_buffer(bh[i]); | |
1063 | continue; | |
1064 | } | |
1065 | get_bh(bh[i]); | |
1066 | bh[i]->b_end_io = end_buffer_read_sync; | |
1067 | submit_bh(READ, bh[i]); | |
1068 | mb_debug("read bitmap for group %lu\n", first_group + i); | |
1069 | } | |
1070 | ||
1071 | /* wait for I/O completion */ | |
1072 | for (i = 0; i < groups_per_page && bh[i]; i++) | |
1073 | wait_on_buffer(bh[i]); | |
1074 | ||
1075 | err = -EIO; | |
1076 | for (i = 0; i < groups_per_page && bh[i]; i++) | |
1077 | if (!buffer_uptodate(bh[i])) | |
1078 | goto out; | |
1079 | ||
1080 | first_block = page->index * blocks_per_page; | |
1081 | for (i = 0; i < blocks_per_page; i++) { | |
1082 | int group; | |
1083 | struct ext4_group_info *grinfo; | |
1084 | ||
1085 | group = (first_block + i) >> 1; | |
1086 | if (group >= EXT4_SB(sb)->s_groups_count) | |
1087 | break; | |
1088 | ||
1089 | /* | |
1090 | * data carry information regarding this | |
1091 | * particular group in the format specified | |
1092 | * above | |
1093 | * | |
1094 | */ | |
1095 | data = page_address(page) + (i * blocksize); | |
1096 | bitmap = bh[group - first_group]->b_data; | |
1097 | ||
1098 | /* | |
1099 | * We place the buddy block and bitmap block | |
1100 | * close together | |
1101 | */ | |
1102 | if ((first_block + i) & 1) { | |
1103 | /* this is block of buddy */ | |
1104 | BUG_ON(incore == NULL); | |
1105 | mb_debug("put buddy for group %u in page %lu/%x\n", | |
1106 | group, page->index, i * blocksize); | |
1107 | memset(data, 0xff, blocksize); | |
1108 | grinfo = ext4_get_group_info(sb, group); | |
1109 | grinfo->bb_fragments = 0; | |
1110 | memset(grinfo->bb_counters, 0, | |
1111 | sizeof(unsigned short)*(sb->s_blocksize_bits+2)); | |
1112 | /* | |
1113 | * incore got set to the group block bitmap below | |
1114 | */ | |
1115 | ext4_mb_generate_buddy(sb, data, incore, group); | |
1116 | incore = NULL; | |
1117 | } else { | |
1118 | /* this is block of bitmap */ | |
1119 | BUG_ON(incore != NULL); | |
1120 | mb_debug("put bitmap for group %u in page %lu/%x\n", | |
1121 | group, page->index, i * blocksize); | |
1122 | ||
1123 | /* see comments in ext4_mb_put_pa() */ | |
1124 | ext4_lock_group(sb, group); | |
1125 | memcpy(data, bitmap, blocksize); | |
1126 | ||
1127 | /* mark all preallocated blks used in in-core bitmap */ | |
1128 | ext4_mb_generate_from_pa(sb, data, group); | |
1129 | ext4_unlock_group(sb, group); | |
1130 | ||
1131 | /* set incore so that the buddy information can be | |
1132 | * generated using this | |
1133 | */ | |
1134 | incore = data; | |
1135 | } | |
1136 | } | |
1137 | SetPageUptodate(page); | |
1138 | ||
1139 | out: | |
1140 | if (bh) { | |
1141 | for (i = 0; i < groups_per_page && bh[i]; i++) | |
1142 | brelse(bh[i]); | |
1143 | if (bh != &bhs) | |
1144 | kfree(bh); | |
1145 | } | |
1146 | return err; | |
1147 | } | |
1148 | ||
1149 | static int ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group, | |
1150 | struct ext4_buddy *e4b) | |
1151 | { | |
1152 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
1153 | struct inode *inode = sbi->s_buddy_cache; | |
1154 | int blocks_per_page; | |
1155 | int block; | |
1156 | int pnum; | |
1157 | int poff; | |
1158 | struct page *page; | |
1159 | ||
1160 | mb_debug("load group %lu\n", group); | |
1161 | ||
1162 | blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; | |
1163 | ||
1164 | e4b->bd_blkbits = sb->s_blocksize_bits; | |
1165 | e4b->bd_info = ext4_get_group_info(sb, group); | |
1166 | e4b->bd_sb = sb; | |
1167 | e4b->bd_group = group; | |
1168 | e4b->bd_buddy_page = NULL; | |
1169 | e4b->bd_bitmap_page = NULL; | |
1170 | ||
1171 | /* | |
1172 | * the buddy cache inode stores the block bitmap | |
1173 | * and buddy information in consecutive blocks. | |
1174 | * So for each group we need two blocks. | |
1175 | */ | |
1176 | block = group * 2; | |
1177 | pnum = block / blocks_per_page; | |
1178 | poff = block % blocks_per_page; | |
1179 | ||
1180 | /* we could use find_or_create_page(), but it locks page | |
1181 | * what we'd like to avoid in fast path ... */ | |
1182 | page = find_get_page(inode->i_mapping, pnum); | |
1183 | if (page == NULL || !PageUptodate(page)) { | |
1184 | if (page) | |
1185 | page_cache_release(page); | |
1186 | page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS); | |
1187 | if (page) { | |
1188 | BUG_ON(page->mapping != inode->i_mapping); | |
1189 | if (!PageUptodate(page)) { | |
1190 | ext4_mb_init_cache(page, NULL); | |
1191 | mb_cmp_bitmaps(e4b, page_address(page) + | |
1192 | (poff * sb->s_blocksize)); | |
1193 | } | |
1194 | unlock_page(page); | |
1195 | } | |
1196 | } | |
1197 | if (page == NULL || !PageUptodate(page)) | |
1198 | goto err; | |
1199 | e4b->bd_bitmap_page = page; | |
1200 | e4b->bd_bitmap = page_address(page) + (poff * sb->s_blocksize); | |
1201 | mark_page_accessed(page); | |
1202 | ||
1203 | block++; | |
1204 | pnum = block / blocks_per_page; | |
1205 | poff = block % blocks_per_page; | |
1206 | ||
1207 | page = find_get_page(inode->i_mapping, pnum); | |
1208 | if (page == NULL || !PageUptodate(page)) { | |
1209 | if (page) | |
1210 | page_cache_release(page); | |
1211 | page = find_or_create_page(inode->i_mapping, pnum, GFP_NOFS); | |
1212 | if (page) { | |
1213 | BUG_ON(page->mapping != inode->i_mapping); | |
1214 | if (!PageUptodate(page)) | |
1215 | ext4_mb_init_cache(page, e4b->bd_bitmap); | |
1216 | ||
1217 | unlock_page(page); | |
1218 | } | |
1219 | } | |
1220 | if (page == NULL || !PageUptodate(page)) | |
1221 | goto err; | |
1222 | e4b->bd_buddy_page = page; | |
1223 | e4b->bd_buddy = page_address(page) + (poff * sb->s_blocksize); | |
1224 | mark_page_accessed(page); | |
1225 | ||
1226 | BUG_ON(e4b->bd_bitmap_page == NULL); | |
1227 | BUG_ON(e4b->bd_buddy_page == NULL); | |
1228 | ||
1229 | return 0; | |
1230 | ||
1231 | err: | |
1232 | if (e4b->bd_bitmap_page) | |
1233 | page_cache_release(e4b->bd_bitmap_page); | |
1234 | if (e4b->bd_buddy_page) | |
1235 | page_cache_release(e4b->bd_buddy_page); | |
1236 | e4b->bd_buddy = NULL; | |
1237 | e4b->bd_bitmap = NULL; | |
1238 | return -EIO; | |
1239 | } | |
1240 | ||
1241 | static void ext4_mb_release_desc(struct ext4_buddy *e4b) | |
1242 | { | |
1243 | if (e4b->bd_bitmap_page) | |
1244 | page_cache_release(e4b->bd_bitmap_page); | |
1245 | if (e4b->bd_buddy_page) | |
1246 | page_cache_release(e4b->bd_buddy_page); | |
1247 | } | |
1248 | ||
1249 | ||
1250 | static int mb_find_order_for_block(struct ext4_buddy *e4b, int block) | |
1251 | { | |
1252 | int order = 1; | |
1253 | void *bb; | |
1254 | ||
1255 | BUG_ON(EXT4_MB_BITMAP(e4b) == EXT4_MB_BUDDY(e4b)); | |
1256 | BUG_ON(block >= (1 << (e4b->bd_blkbits + 3))); | |
1257 | ||
1258 | bb = EXT4_MB_BUDDY(e4b); | |
1259 | while (order <= e4b->bd_blkbits + 1) { | |
1260 | block = block >> 1; | |
1261 | if (!mb_test_bit(block, bb)) { | |
1262 | /* this block is part of buddy of order 'order' */ | |
1263 | return order; | |
1264 | } | |
1265 | bb += 1 << (e4b->bd_blkbits - order); | |
1266 | order++; | |
1267 | } | |
1268 | return 0; | |
1269 | } | |
1270 | ||
1271 | static void mb_clear_bits(spinlock_t *lock, void *bm, int cur, int len) | |
1272 | { | |
1273 | __u32 *addr; | |
1274 | ||
1275 | len = cur + len; | |
1276 | while (cur < len) { | |
1277 | if ((cur & 31) == 0 && (len - cur) >= 32) { | |
1278 | /* fast path: clear whole word at once */ | |
1279 | addr = bm + (cur >> 3); | |
1280 | *addr = 0; | |
1281 | cur += 32; | |
1282 | continue; | |
1283 | } | |
1284 | mb_clear_bit_atomic(lock, cur, bm); | |
1285 | cur++; | |
1286 | } | |
1287 | } | |
1288 | ||
1289 | static void mb_set_bits(spinlock_t *lock, void *bm, int cur, int len) | |
1290 | { | |
1291 | __u32 *addr; | |
1292 | ||
1293 | len = cur + len; | |
1294 | while (cur < len) { | |
1295 | if ((cur & 31) == 0 && (len - cur) >= 32) { | |
1296 | /* fast path: set whole word at once */ | |
1297 | addr = bm + (cur >> 3); | |
1298 | *addr = 0xffffffff; | |
1299 | cur += 32; | |
1300 | continue; | |
1301 | } | |
1302 | mb_set_bit_atomic(lock, cur, bm); | |
1303 | cur++; | |
1304 | } | |
1305 | } | |
1306 | ||
1307 | static int mb_free_blocks(struct inode *inode, struct ext4_buddy *e4b, | |
1308 | int first, int count) | |
1309 | { | |
1310 | int block = 0; | |
1311 | int max = 0; | |
1312 | int order; | |
1313 | void *buddy; | |
1314 | void *buddy2; | |
1315 | struct super_block *sb = e4b->bd_sb; | |
1316 | ||
1317 | BUG_ON(first + count > (sb->s_blocksize << 3)); | |
1318 | BUG_ON(!ext4_is_group_locked(sb, e4b->bd_group)); | |
1319 | mb_check_buddy(e4b); | |
1320 | mb_free_blocks_double(inode, e4b, first, count); | |
1321 | ||
1322 | e4b->bd_info->bb_free += count; | |
1323 | if (first < e4b->bd_info->bb_first_free) | |
1324 | e4b->bd_info->bb_first_free = first; | |
1325 | ||
1326 | /* let's maintain fragments counter */ | |
1327 | if (first != 0) | |
1328 | block = !mb_test_bit(first - 1, EXT4_MB_BITMAP(e4b)); | |
1329 | if (first + count < EXT4_SB(sb)->s_mb_maxs[0]) | |
1330 | max = !mb_test_bit(first + count, EXT4_MB_BITMAP(e4b)); | |
1331 | if (block && max) | |
1332 | e4b->bd_info->bb_fragments--; | |
1333 | else if (!block && !max) | |
1334 | e4b->bd_info->bb_fragments++; | |
1335 | ||
1336 | /* let's maintain buddy itself */ | |
1337 | while (count-- > 0) { | |
1338 | block = first++; | |
1339 | order = 0; | |
1340 | ||
1341 | if (!mb_test_bit(block, EXT4_MB_BITMAP(e4b))) { | |
1342 | ext4_fsblk_t blocknr; | |
1343 | blocknr = e4b->bd_group * EXT4_BLOCKS_PER_GROUP(sb); | |
1344 | blocknr += block; | |
1345 | blocknr += | |
1346 | le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block); | |
1347 | ||
1348 | ext4_error(sb, __FUNCTION__, "double-free of inode" | |
1349 | " %lu's block %llu(bit %u in group %lu)\n", | |
1350 | inode ? inode->i_ino : 0, blocknr, block, | |
1351 | e4b->bd_group); | |
1352 | } | |
1353 | mb_clear_bit(block, EXT4_MB_BITMAP(e4b)); | |
1354 | e4b->bd_info->bb_counters[order]++; | |
1355 | ||
1356 | /* start of the buddy */ | |
1357 | buddy = mb_find_buddy(e4b, order, &max); | |
1358 | ||
1359 | do { | |
1360 | block &= ~1UL; | |
1361 | if (mb_test_bit(block, buddy) || | |
1362 | mb_test_bit(block + 1, buddy)) | |
1363 | break; | |
1364 | ||
1365 | /* both the buddies are free, try to coalesce them */ | |
1366 | buddy2 = mb_find_buddy(e4b, order + 1, &max); | |
1367 | ||
1368 | if (!buddy2) | |
1369 | break; | |
1370 | ||
1371 | if (order > 0) { | |
1372 | /* for special purposes, we don't set | |
1373 | * free bits in bitmap */ | |
1374 | mb_set_bit(block, buddy); | |
1375 | mb_set_bit(block + 1, buddy); | |
1376 | } | |
1377 | e4b->bd_info->bb_counters[order]--; | |
1378 | e4b->bd_info->bb_counters[order]--; | |
1379 | ||
1380 | block = block >> 1; | |
1381 | order++; | |
1382 | e4b->bd_info->bb_counters[order]++; | |
1383 | ||
1384 | mb_clear_bit(block, buddy2); | |
1385 | buddy = buddy2; | |
1386 | } while (1); | |
1387 | } | |
1388 | mb_check_buddy(e4b); | |
1389 | ||
1390 | return 0; | |
1391 | } | |
1392 | ||
1393 | static int mb_find_extent(struct ext4_buddy *e4b, int order, int block, | |
1394 | int needed, struct ext4_free_extent *ex) | |
1395 | { | |
1396 | int next = block; | |
1397 | int max; | |
1398 | int ord; | |
1399 | void *buddy; | |
1400 | ||
1401 | BUG_ON(!ext4_is_group_locked(e4b->bd_sb, e4b->bd_group)); | |
1402 | BUG_ON(ex == NULL); | |
1403 | ||
1404 | buddy = mb_find_buddy(e4b, order, &max); | |
1405 | BUG_ON(buddy == NULL); | |
1406 | BUG_ON(block >= max); | |
1407 | if (mb_test_bit(block, buddy)) { | |
1408 | ex->fe_len = 0; | |
1409 | ex->fe_start = 0; | |
1410 | ex->fe_group = 0; | |
1411 | return 0; | |
1412 | } | |
1413 | ||
1414 | /* FIXME dorp order completely ? */ | |
1415 | if (likely(order == 0)) { | |
1416 | /* find actual order */ | |
1417 | order = mb_find_order_for_block(e4b, block); | |
1418 | block = block >> order; | |
1419 | } | |
1420 | ||
1421 | ex->fe_len = 1 << order; | |
1422 | ex->fe_start = block << order; | |
1423 | ex->fe_group = e4b->bd_group; | |
1424 | ||
1425 | /* calc difference from given start */ | |
1426 | next = next - ex->fe_start; | |
1427 | ex->fe_len -= next; | |
1428 | ex->fe_start += next; | |
1429 | ||
1430 | while (needed > ex->fe_len && | |
1431 | (buddy = mb_find_buddy(e4b, order, &max))) { | |
1432 | ||
1433 | if (block + 1 >= max) | |
1434 | break; | |
1435 | ||
1436 | next = (block + 1) * (1 << order); | |
1437 | if (mb_test_bit(next, EXT4_MB_BITMAP(e4b))) | |
1438 | break; | |
1439 | ||
1440 | ord = mb_find_order_for_block(e4b, next); | |
1441 | ||
1442 | order = ord; | |
1443 | block = next >> order; | |
1444 | ex->fe_len += 1 << order; | |
1445 | } | |
1446 | ||
1447 | BUG_ON(ex->fe_start + ex->fe_len > (1 << (e4b->bd_blkbits + 3))); | |
1448 | return ex->fe_len; | |
1449 | } | |
1450 | ||
1451 | static int mb_mark_used(struct ext4_buddy *e4b, struct ext4_free_extent *ex) | |
1452 | { | |
1453 | int ord; | |
1454 | int mlen = 0; | |
1455 | int max = 0; | |
1456 | int cur; | |
1457 | int start = ex->fe_start; | |
1458 | int len = ex->fe_len; | |
1459 | unsigned ret = 0; | |
1460 | int len0 = len; | |
1461 | void *buddy; | |
1462 | ||
1463 | BUG_ON(start + len > (e4b->bd_sb->s_blocksize << 3)); | |
1464 | BUG_ON(e4b->bd_group != ex->fe_group); | |
1465 | BUG_ON(!ext4_is_group_locked(e4b->bd_sb, e4b->bd_group)); | |
1466 | mb_check_buddy(e4b); | |
1467 | mb_mark_used_double(e4b, start, len); | |
1468 | ||
1469 | e4b->bd_info->bb_free -= len; | |
1470 | if (e4b->bd_info->bb_first_free == start) | |
1471 | e4b->bd_info->bb_first_free += len; | |
1472 | ||
1473 | /* let's maintain fragments counter */ | |
1474 | if (start != 0) | |
1475 | mlen = !mb_test_bit(start - 1, EXT4_MB_BITMAP(e4b)); | |
1476 | if (start + len < EXT4_SB(e4b->bd_sb)->s_mb_maxs[0]) | |
1477 | max = !mb_test_bit(start + len, EXT4_MB_BITMAP(e4b)); | |
1478 | if (mlen && max) | |
1479 | e4b->bd_info->bb_fragments++; | |
1480 | else if (!mlen && !max) | |
1481 | e4b->bd_info->bb_fragments--; | |
1482 | ||
1483 | /* let's maintain buddy itself */ | |
1484 | while (len) { | |
1485 | ord = mb_find_order_for_block(e4b, start); | |
1486 | ||
1487 | if (((start >> ord) << ord) == start && len >= (1 << ord)) { | |
1488 | /* the whole chunk may be allocated at once! */ | |
1489 | mlen = 1 << ord; | |
1490 | buddy = mb_find_buddy(e4b, ord, &max); | |
1491 | BUG_ON((start >> ord) >= max); | |
1492 | mb_set_bit(start >> ord, buddy); | |
1493 | e4b->bd_info->bb_counters[ord]--; | |
1494 | start += mlen; | |
1495 | len -= mlen; | |
1496 | BUG_ON(len < 0); | |
1497 | continue; | |
1498 | } | |
1499 | ||
1500 | /* store for history */ | |
1501 | if (ret == 0) | |
1502 | ret = len | (ord << 16); | |
1503 | ||
1504 | /* we have to split large buddy */ | |
1505 | BUG_ON(ord <= 0); | |
1506 | buddy = mb_find_buddy(e4b, ord, &max); | |
1507 | mb_set_bit(start >> ord, buddy); | |
1508 | e4b->bd_info->bb_counters[ord]--; | |
1509 | ||
1510 | ord--; | |
1511 | cur = (start >> ord) & ~1U; | |
1512 | buddy = mb_find_buddy(e4b, ord, &max); | |
1513 | mb_clear_bit(cur, buddy); | |
1514 | mb_clear_bit(cur + 1, buddy); | |
1515 | e4b->bd_info->bb_counters[ord]++; | |
1516 | e4b->bd_info->bb_counters[ord]++; | |
1517 | } | |
1518 | ||
1519 | mb_set_bits(sb_bgl_lock(EXT4_SB(e4b->bd_sb), ex->fe_group), | |
1520 | EXT4_MB_BITMAP(e4b), ex->fe_start, len0); | |
1521 | mb_check_buddy(e4b); | |
1522 | ||
1523 | return ret; | |
1524 | } | |
1525 | ||
1526 | /* | |
1527 | * Must be called under group lock! | |
1528 | */ | |
1529 | static void ext4_mb_use_best_found(struct ext4_allocation_context *ac, | |
1530 | struct ext4_buddy *e4b) | |
1531 | { | |
1532 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
1533 | int ret; | |
1534 | ||
1535 | BUG_ON(ac->ac_b_ex.fe_group != e4b->bd_group); | |
1536 | BUG_ON(ac->ac_status == AC_STATUS_FOUND); | |
1537 | ||
1538 | ac->ac_b_ex.fe_len = min(ac->ac_b_ex.fe_len, ac->ac_g_ex.fe_len); | |
1539 | ac->ac_b_ex.fe_logical = ac->ac_g_ex.fe_logical; | |
1540 | ret = mb_mark_used(e4b, &ac->ac_b_ex); | |
1541 | ||
1542 | /* preallocation can change ac_b_ex, thus we store actually | |
1543 | * allocated blocks for history */ | |
1544 | ac->ac_f_ex = ac->ac_b_ex; | |
1545 | ||
1546 | ac->ac_status = AC_STATUS_FOUND; | |
1547 | ac->ac_tail = ret & 0xffff; | |
1548 | ac->ac_buddy = ret >> 16; | |
1549 | ||
1550 | /* XXXXXXX: SUCH A HORRIBLE **CK */ | |
1551 | /*FIXME!! Why ? */ | |
1552 | ac->ac_bitmap_page = e4b->bd_bitmap_page; | |
1553 | get_page(ac->ac_bitmap_page); | |
1554 | ac->ac_buddy_page = e4b->bd_buddy_page; | |
1555 | get_page(ac->ac_buddy_page); | |
1556 | ||
1557 | /* store last allocated for subsequent stream allocation */ | |
1558 | if ((ac->ac_flags & EXT4_MB_HINT_DATA)) { | |
1559 | spin_lock(&sbi->s_md_lock); | |
1560 | sbi->s_mb_last_group = ac->ac_f_ex.fe_group; | |
1561 | sbi->s_mb_last_start = ac->ac_f_ex.fe_start; | |
1562 | spin_unlock(&sbi->s_md_lock); | |
1563 | } | |
1564 | } | |
1565 | ||
1566 | /* | |
1567 | * regular allocator, for general purposes allocation | |
1568 | */ | |
1569 | ||
1570 | static void ext4_mb_check_limits(struct ext4_allocation_context *ac, | |
1571 | struct ext4_buddy *e4b, | |
1572 | int finish_group) | |
1573 | { | |
1574 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
1575 | struct ext4_free_extent *bex = &ac->ac_b_ex; | |
1576 | struct ext4_free_extent *gex = &ac->ac_g_ex; | |
1577 | struct ext4_free_extent ex; | |
1578 | int max; | |
1579 | ||
1580 | /* | |
1581 | * We don't want to scan for a whole year | |
1582 | */ | |
1583 | if (ac->ac_found > sbi->s_mb_max_to_scan && | |
1584 | !(ac->ac_flags & EXT4_MB_HINT_FIRST)) { | |
1585 | ac->ac_status = AC_STATUS_BREAK; | |
1586 | return; | |
1587 | } | |
1588 | ||
1589 | /* | |
1590 | * Haven't found good chunk so far, let's continue | |
1591 | */ | |
1592 | if (bex->fe_len < gex->fe_len) | |
1593 | return; | |
1594 | ||
1595 | if ((finish_group || ac->ac_found > sbi->s_mb_min_to_scan) | |
1596 | && bex->fe_group == e4b->bd_group) { | |
1597 | /* recheck chunk's availability - we don't know | |
1598 | * when it was found (within this lock-unlock | |
1599 | * period or not) */ | |
1600 | max = mb_find_extent(e4b, 0, bex->fe_start, gex->fe_len, &ex); | |
1601 | if (max >= gex->fe_len) { | |
1602 | ext4_mb_use_best_found(ac, e4b); | |
1603 | return; | |
1604 | } | |
1605 | } | |
1606 | } | |
1607 | ||
1608 | /* | |
1609 | * The routine checks whether found extent is good enough. If it is, | |
1610 | * then the extent gets marked used and flag is set to the context | |
1611 | * to stop scanning. Otherwise, the extent is compared with the | |
1612 | * previous found extent and if new one is better, then it's stored | |
1613 | * in the context. Later, the best found extent will be used, if | |
1614 | * mballoc can't find good enough extent. | |
1615 | * | |
1616 | * FIXME: real allocation policy is to be designed yet! | |
1617 | */ | |
1618 | static void ext4_mb_measure_extent(struct ext4_allocation_context *ac, | |
1619 | struct ext4_free_extent *ex, | |
1620 | struct ext4_buddy *e4b) | |
1621 | { | |
1622 | struct ext4_free_extent *bex = &ac->ac_b_ex; | |
1623 | struct ext4_free_extent *gex = &ac->ac_g_ex; | |
1624 | ||
1625 | BUG_ON(ex->fe_len <= 0); | |
1626 | BUG_ON(ex->fe_len >= EXT4_BLOCKS_PER_GROUP(ac->ac_sb)); | |
1627 | BUG_ON(ex->fe_start >= EXT4_BLOCKS_PER_GROUP(ac->ac_sb)); | |
1628 | BUG_ON(ac->ac_status != AC_STATUS_CONTINUE); | |
1629 | ||
1630 | ac->ac_found++; | |
1631 | ||
1632 | /* | |
1633 | * The special case - take what you catch first | |
1634 | */ | |
1635 | if (unlikely(ac->ac_flags & EXT4_MB_HINT_FIRST)) { | |
1636 | *bex = *ex; | |
1637 | ext4_mb_use_best_found(ac, e4b); | |
1638 | return; | |
1639 | } | |
1640 | ||
1641 | /* | |
1642 | * Let's check whether the chuck is good enough | |
1643 | */ | |
1644 | if (ex->fe_len == gex->fe_len) { | |
1645 | *bex = *ex; | |
1646 | ext4_mb_use_best_found(ac, e4b); | |
1647 | return; | |
1648 | } | |
1649 | ||
1650 | /* | |
1651 | * If this is first found extent, just store it in the context | |
1652 | */ | |
1653 | if (bex->fe_len == 0) { | |
1654 | *bex = *ex; | |
1655 | return; | |
1656 | } | |
1657 | ||
1658 | /* | |
1659 | * If new found extent is better, store it in the context | |
1660 | */ | |
1661 | if (bex->fe_len < gex->fe_len) { | |
1662 | /* if the request isn't satisfied, any found extent | |
1663 | * larger than previous best one is better */ | |
1664 | if (ex->fe_len > bex->fe_len) | |
1665 | *bex = *ex; | |
1666 | } else if (ex->fe_len > gex->fe_len) { | |
1667 | /* if the request is satisfied, then we try to find | |
1668 | * an extent that still satisfy the request, but is | |
1669 | * smaller than previous one */ | |
1670 | if (ex->fe_len < bex->fe_len) | |
1671 | *bex = *ex; | |
1672 | } | |
1673 | ||
1674 | ext4_mb_check_limits(ac, e4b, 0); | |
1675 | } | |
1676 | ||
1677 | static int ext4_mb_try_best_found(struct ext4_allocation_context *ac, | |
1678 | struct ext4_buddy *e4b) | |
1679 | { | |
1680 | struct ext4_free_extent ex = ac->ac_b_ex; | |
1681 | ext4_group_t group = ex.fe_group; | |
1682 | int max; | |
1683 | int err; | |
1684 | ||
1685 | BUG_ON(ex.fe_len <= 0); | |
1686 | err = ext4_mb_load_buddy(ac->ac_sb, group, e4b); | |
1687 | if (err) | |
1688 | return err; | |
1689 | ||
1690 | ext4_lock_group(ac->ac_sb, group); | |
1691 | max = mb_find_extent(e4b, 0, ex.fe_start, ex.fe_len, &ex); | |
1692 | ||
1693 | if (max > 0) { | |
1694 | ac->ac_b_ex = ex; | |
1695 | ext4_mb_use_best_found(ac, e4b); | |
1696 | } | |
1697 | ||
1698 | ext4_unlock_group(ac->ac_sb, group); | |
1699 | ext4_mb_release_desc(e4b); | |
1700 | ||
1701 | return 0; | |
1702 | } | |
1703 | ||
1704 | static int ext4_mb_find_by_goal(struct ext4_allocation_context *ac, | |
1705 | struct ext4_buddy *e4b) | |
1706 | { | |
1707 | ext4_group_t group = ac->ac_g_ex.fe_group; | |
1708 | int max; | |
1709 | int err; | |
1710 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
1711 | struct ext4_super_block *es = sbi->s_es; | |
1712 | struct ext4_free_extent ex; | |
1713 | ||
1714 | if (!(ac->ac_flags & EXT4_MB_HINT_TRY_GOAL)) | |
1715 | return 0; | |
1716 | ||
1717 | err = ext4_mb_load_buddy(ac->ac_sb, group, e4b); | |
1718 | if (err) | |
1719 | return err; | |
1720 | ||
1721 | ext4_lock_group(ac->ac_sb, group); | |
1722 | max = mb_find_extent(e4b, 0, ac->ac_g_ex.fe_start, | |
1723 | ac->ac_g_ex.fe_len, &ex); | |
1724 | ||
1725 | if (max >= ac->ac_g_ex.fe_len && ac->ac_g_ex.fe_len == sbi->s_stripe) { | |
1726 | ext4_fsblk_t start; | |
1727 | ||
1728 | start = (e4b->bd_group * EXT4_BLOCKS_PER_GROUP(ac->ac_sb)) + | |
1729 | ex.fe_start + le32_to_cpu(es->s_first_data_block); | |
1730 | /* use do_div to get remainder (would be 64-bit modulo) */ | |
1731 | if (do_div(start, sbi->s_stripe) == 0) { | |
1732 | ac->ac_found++; | |
1733 | ac->ac_b_ex = ex; | |
1734 | ext4_mb_use_best_found(ac, e4b); | |
1735 | } | |
1736 | } else if (max >= ac->ac_g_ex.fe_len) { | |
1737 | BUG_ON(ex.fe_len <= 0); | |
1738 | BUG_ON(ex.fe_group != ac->ac_g_ex.fe_group); | |
1739 | BUG_ON(ex.fe_start != ac->ac_g_ex.fe_start); | |
1740 | ac->ac_found++; | |
1741 | ac->ac_b_ex = ex; | |
1742 | ext4_mb_use_best_found(ac, e4b); | |
1743 | } else if (max > 0 && (ac->ac_flags & EXT4_MB_HINT_MERGE)) { | |
1744 | /* Sometimes, caller may want to merge even small | |
1745 | * number of blocks to an existing extent */ | |
1746 | BUG_ON(ex.fe_len <= 0); | |
1747 | BUG_ON(ex.fe_group != ac->ac_g_ex.fe_group); | |
1748 | BUG_ON(ex.fe_start != ac->ac_g_ex.fe_start); | |
1749 | ac->ac_found++; | |
1750 | ac->ac_b_ex = ex; | |
1751 | ext4_mb_use_best_found(ac, e4b); | |
1752 | } | |
1753 | ext4_unlock_group(ac->ac_sb, group); | |
1754 | ext4_mb_release_desc(e4b); | |
1755 | ||
1756 | return 0; | |
1757 | } | |
1758 | ||
1759 | /* | |
1760 | * The routine scans buddy structures (not bitmap!) from given order | |
1761 | * to max order and tries to find big enough chunk to satisfy the req | |
1762 | */ | |
1763 | static void ext4_mb_simple_scan_group(struct ext4_allocation_context *ac, | |
1764 | struct ext4_buddy *e4b) | |
1765 | { | |
1766 | struct super_block *sb = ac->ac_sb; | |
1767 | struct ext4_group_info *grp = e4b->bd_info; | |
1768 | void *buddy; | |
1769 | int i; | |
1770 | int k; | |
1771 | int max; | |
1772 | ||
1773 | BUG_ON(ac->ac_2order <= 0); | |
1774 | for (i = ac->ac_2order; i <= sb->s_blocksize_bits + 1; i++) { | |
1775 | if (grp->bb_counters[i] == 0) | |
1776 | continue; | |
1777 | ||
1778 | buddy = mb_find_buddy(e4b, i, &max); | |
1779 | BUG_ON(buddy == NULL); | |
1780 | ||
1781 | k = ext4_find_next_zero_bit(buddy, max, 0); | |
1782 | BUG_ON(k >= max); | |
1783 | ||
1784 | ac->ac_found++; | |
1785 | ||
1786 | ac->ac_b_ex.fe_len = 1 << i; | |
1787 | ac->ac_b_ex.fe_start = k << i; | |
1788 | ac->ac_b_ex.fe_group = e4b->bd_group; | |
1789 | ||
1790 | ext4_mb_use_best_found(ac, e4b); | |
1791 | ||
1792 | BUG_ON(ac->ac_b_ex.fe_len != ac->ac_g_ex.fe_len); | |
1793 | ||
1794 | if (EXT4_SB(sb)->s_mb_stats) | |
1795 | atomic_inc(&EXT4_SB(sb)->s_bal_2orders); | |
1796 | ||
1797 | break; | |
1798 | } | |
1799 | } | |
1800 | ||
1801 | /* | |
1802 | * The routine scans the group and measures all found extents. | |
1803 | * In order to optimize scanning, caller must pass number of | |
1804 | * free blocks in the group, so the routine can know upper limit. | |
1805 | */ | |
1806 | static void ext4_mb_complex_scan_group(struct ext4_allocation_context *ac, | |
1807 | struct ext4_buddy *e4b) | |
1808 | { | |
1809 | struct super_block *sb = ac->ac_sb; | |
1810 | void *bitmap = EXT4_MB_BITMAP(e4b); | |
1811 | struct ext4_free_extent ex; | |
1812 | int i; | |
1813 | int free; | |
1814 | ||
1815 | free = e4b->bd_info->bb_free; | |
1816 | BUG_ON(free <= 0); | |
1817 | ||
1818 | i = e4b->bd_info->bb_first_free; | |
1819 | ||
1820 | while (free && ac->ac_status == AC_STATUS_CONTINUE) { | |
1821 | i = ext4_find_next_zero_bit(bitmap, | |
1822 | EXT4_BLOCKS_PER_GROUP(sb), i); | |
1823 | if (i >= EXT4_BLOCKS_PER_GROUP(sb)) { | |
26346ff6 AK |
1824 | /* |
1825 | * IF we corrupt the bitmap we won't find any | |
1826 | * free blocks even though group info says we | |
1827 | * we have free blocks | |
1828 | */ | |
1829 | ext4_error(sb, __FUNCTION__, "%d free blocks as per " | |
1830 | "group info. But bitmap says 0\n", | |
1831 | free); | |
c9de560d AT |
1832 | break; |
1833 | } | |
1834 | ||
1835 | mb_find_extent(e4b, 0, i, ac->ac_g_ex.fe_len, &ex); | |
1836 | BUG_ON(ex.fe_len <= 0); | |
26346ff6 AK |
1837 | if (free < ex.fe_len) { |
1838 | ext4_error(sb, __FUNCTION__, "%d free blocks as per " | |
1839 | "group info. But got %d blocks\n", | |
1840 | free, ex.fe_len); | |
1841 | } | |
c9de560d AT |
1842 | |
1843 | ext4_mb_measure_extent(ac, &ex, e4b); | |
1844 | ||
1845 | i += ex.fe_len; | |
1846 | free -= ex.fe_len; | |
1847 | } | |
1848 | ||
1849 | ext4_mb_check_limits(ac, e4b, 1); | |
1850 | } | |
1851 | ||
1852 | /* | |
1853 | * This is a special case for storages like raid5 | |
1854 | * we try to find stripe-aligned chunks for stripe-size requests | |
1855 | * XXX should do so at least for multiples of stripe size as well | |
1856 | */ | |
1857 | static void ext4_mb_scan_aligned(struct ext4_allocation_context *ac, | |
1858 | struct ext4_buddy *e4b) | |
1859 | { | |
1860 | struct super_block *sb = ac->ac_sb; | |
1861 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
1862 | void *bitmap = EXT4_MB_BITMAP(e4b); | |
1863 | struct ext4_free_extent ex; | |
1864 | ext4_fsblk_t first_group_block; | |
1865 | ext4_fsblk_t a; | |
1866 | ext4_grpblk_t i; | |
1867 | int max; | |
1868 | ||
1869 | BUG_ON(sbi->s_stripe == 0); | |
1870 | ||
1871 | /* find first stripe-aligned block in group */ | |
1872 | first_group_block = e4b->bd_group * EXT4_BLOCKS_PER_GROUP(sb) | |
1873 | + le32_to_cpu(sbi->s_es->s_first_data_block); | |
1874 | a = first_group_block + sbi->s_stripe - 1; | |
1875 | do_div(a, sbi->s_stripe); | |
1876 | i = (a * sbi->s_stripe) - first_group_block; | |
1877 | ||
1878 | while (i < EXT4_BLOCKS_PER_GROUP(sb)) { | |
1879 | if (!mb_test_bit(i, bitmap)) { | |
1880 | max = mb_find_extent(e4b, 0, i, sbi->s_stripe, &ex); | |
1881 | if (max >= sbi->s_stripe) { | |
1882 | ac->ac_found++; | |
1883 | ac->ac_b_ex = ex; | |
1884 | ext4_mb_use_best_found(ac, e4b); | |
1885 | break; | |
1886 | } | |
1887 | } | |
1888 | i += sbi->s_stripe; | |
1889 | } | |
1890 | } | |
1891 | ||
1892 | static int ext4_mb_good_group(struct ext4_allocation_context *ac, | |
1893 | ext4_group_t group, int cr) | |
1894 | { | |
1895 | unsigned free, fragments; | |
1896 | unsigned i, bits; | |
1897 | struct ext4_group_desc *desc; | |
1898 | struct ext4_group_info *grp = ext4_get_group_info(ac->ac_sb, group); | |
1899 | ||
1900 | BUG_ON(cr < 0 || cr >= 4); | |
1901 | BUG_ON(EXT4_MB_GRP_NEED_INIT(grp)); | |
1902 | ||
1903 | free = grp->bb_free; | |
1904 | fragments = grp->bb_fragments; | |
1905 | if (free == 0) | |
1906 | return 0; | |
1907 | if (fragments == 0) | |
1908 | return 0; | |
1909 | ||
1910 | switch (cr) { | |
1911 | case 0: | |
1912 | BUG_ON(ac->ac_2order == 0); | |
1913 | /* If this group is uninitialized, skip it initially */ | |
1914 | desc = ext4_get_group_desc(ac->ac_sb, group, NULL); | |
1915 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) | |
1916 | return 0; | |
1917 | ||
1918 | bits = ac->ac_sb->s_blocksize_bits + 1; | |
1919 | for (i = ac->ac_2order; i <= bits; i++) | |
1920 | if (grp->bb_counters[i] > 0) | |
1921 | return 1; | |
1922 | break; | |
1923 | case 1: | |
1924 | if ((free / fragments) >= ac->ac_g_ex.fe_len) | |
1925 | return 1; | |
1926 | break; | |
1927 | case 2: | |
1928 | if (free >= ac->ac_g_ex.fe_len) | |
1929 | return 1; | |
1930 | break; | |
1931 | case 3: | |
1932 | return 1; | |
1933 | default: | |
1934 | BUG(); | |
1935 | } | |
1936 | ||
1937 | return 0; | |
1938 | } | |
1939 | ||
1940 | static int ext4_mb_regular_allocator(struct ext4_allocation_context *ac) | |
1941 | { | |
1942 | ext4_group_t group; | |
1943 | ext4_group_t i; | |
1944 | int cr; | |
1945 | int err = 0; | |
1946 | int bsbits; | |
1947 | struct ext4_sb_info *sbi; | |
1948 | struct super_block *sb; | |
1949 | struct ext4_buddy e4b; | |
1950 | loff_t size, isize; | |
1951 | ||
1952 | sb = ac->ac_sb; | |
1953 | sbi = EXT4_SB(sb); | |
1954 | BUG_ON(ac->ac_status == AC_STATUS_FOUND); | |
1955 | ||
1956 | /* first, try the goal */ | |
1957 | err = ext4_mb_find_by_goal(ac, &e4b); | |
1958 | if (err || ac->ac_status == AC_STATUS_FOUND) | |
1959 | goto out; | |
1960 | ||
1961 | if (unlikely(ac->ac_flags & EXT4_MB_HINT_GOAL_ONLY)) | |
1962 | goto out; | |
1963 | ||
1964 | /* | |
1965 | * ac->ac2_order is set only if the fe_len is a power of 2 | |
1966 | * if ac2_order is set we also set criteria to 0 so that we | |
1967 | * try exact allocation using buddy. | |
1968 | */ | |
1969 | i = fls(ac->ac_g_ex.fe_len); | |
1970 | ac->ac_2order = 0; | |
1971 | /* | |
1972 | * We search using buddy data only if the order of the request | |
1973 | * is greater than equal to the sbi_s_mb_order2_reqs | |
1974 | * You can tune it via /proc/fs/ext4/<partition>/order2_req | |
1975 | */ | |
1976 | if (i >= sbi->s_mb_order2_reqs) { | |
1977 | /* | |
1978 | * This should tell if fe_len is exactly power of 2 | |
1979 | */ | |
1980 | if ((ac->ac_g_ex.fe_len & (~(1 << (i - 1)))) == 0) | |
1981 | ac->ac_2order = i - 1; | |
1982 | } | |
1983 | ||
1984 | bsbits = ac->ac_sb->s_blocksize_bits; | |
1985 | /* if stream allocation is enabled, use global goal */ | |
1986 | size = ac->ac_o_ex.fe_logical + ac->ac_o_ex.fe_len; | |
1987 | isize = i_size_read(ac->ac_inode) >> bsbits; | |
1988 | if (size < isize) | |
1989 | size = isize; | |
1990 | ||
1991 | if (size < sbi->s_mb_stream_request && | |
1992 | (ac->ac_flags & EXT4_MB_HINT_DATA)) { | |
1993 | /* TBD: may be hot point */ | |
1994 | spin_lock(&sbi->s_md_lock); | |
1995 | ac->ac_g_ex.fe_group = sbi->s_mb_last_group; | |
1996 | ac->ac_g_ex.fe_start = sbi->s_mb_last_start; | |
1997 | spin_unlock(&sbi->s_md_lock); | |
1998 | } | |
1999 | ||
2000 | /* searching for the right group start from the goal value specified */ | |
2001 | group = ac->ac_g_ex.fe_group; | |
2002 | ||
2003 | /* Let's just scan groups to find more-less suitable blocks */ | |
2004 | cr = ac->ac_2order ? 0 : 1; | |
2005 | /* | |
2006 | * cr == 0 try to get exact allocation, | |
2007 | * cr == 3 try to get anything | |
2008 | */ | |
2009 | repeat: | |
2010 | for (; cr < 4 && ac->ac_status == AC_STATUS_CONTINUE; cr++) { | |
2011 | ac->ac_criteria = cr; | |
2012 | for (i = 0; i < EXT4_SB(sb)->s_groups_count; group++, i++) { | |
2013 | struct ext4_group_info *grp; | |
2014 | struct ext4_group_desc *desc; | |
2015 | ||
2016 | if (group == EXT4_SB(sb)->s_groups_count) | |
2017 | group = 0; | |
2018 | ||
2019 | /* quick check to skip empty groups */ | |
2020 | grp = ext4_get_group_info(ac->ac_sb, group); | |
2021 | if (grp->bb_free == 0) | |
2022 | continue; | |
2023 | ||
2024 | /* | |
2025 | * if the group is already init we check whether it is | |
2026 | * a good group and if not we don't load the buddy | |
2027 | */ | |
2028 | if (EXT4_MB_GRP_NEED_INIT(grp)) { | |
2029 | /* | |
2030 | * we need full data about the group | |
2031 | * to make a good selection | |
2032 | */ | |
2033 | err = ext4_mb_load_buddy(sb, group, &e4b); | |
2034 | if (err) | |
2035 | goto out; | |
2036 | ext4_mb_release_desc(&e4b); | |
2037 | } | |
2038 | ||
2039 | /* | |
2040 | * If the particular group doesn't satisfy our | |
2041 | * criteria we continue with the next group | |
2042 | */ | |
2043 | if (!ext4_mb_good_group(ac, group, cr)) | |
2044 | continue; | |
2045 | ||
2046 | err = ext4_mb_load_buddy(sb, group, &e4b); | |
2047 | if (err) | |
2048 | goto out; | |
2049 | ||
2050 | ext4_lock_group(sb, group); | |
2051 | if (!ext4_mb_good_group(ac, group, cr)) { | |
2052 | /* someone did allocation from this group */ | |
2053 | ext4_unlock_group(sb, group); | |
2054 | ext4_mb_release_desc(&e4b); | |
2055 | continue; | |
2056 | } | |
2057 | ||
2058 | ac->ac_groups_scanned++; | |
2059 | desc = ext4_get_group_desc(sb, group, NULL); | |
2060 | if (cr == 0 || (desc->bg_flags & | |
2061 | cpu_to_le16(EXT4_BG_BLOCK_UNINIT) && | |
2062 | ac->ac_2order != 0)) | |
2063 | ext4_mb_simple_scan_group(ac, &e4b); | |
2064 | else if (cr == 1 && | |
2065 | ac->ac_g_ex.fe_len == sbi->s_stripe) | |
2066 | ext4_mb_scan_aligned(ac, &e4b); | |
2067 | else | |
2068 | ext4_mb_complex_scan_group(ac, &e4b); | |
2069 | ||
2070 | ext4_unlock_group(sb, group); | |
2071 | ext4_mb_release_desc(&e4b); | |
2072 | ||
2073 | if (ac->ac_status != AC_STATUS_CONTINUE) | |
2074 | break; | |
2075 | } | |
2076 | } | |
2077 | ||
2078 | if (ac->ac_b_ex.fe_len > 0 && ac->ac_status != AC_STATUS_FOUND && | |
2079 | !(ac->ac_flags & EXT4_MB_HINT_FIRST)) { | |
2080 | /* | |
2081 | * We've been searching too long. Let's try to allocate | |
2082 | * the best chunk we've found so far | |
2083 | */ | |
2084 | ||
2085 | ext4_mb_try_best_found(ac, &e4b); | |
2086 | if (ac->ac_status != AC_STATUS_FOUND) { | |
2087 | /* | |
2088 | * Someone more lucky has already allocated it. | |
2089 | * The only thing we can do is just take first | |
2090 | * found block(s) | |
2091 | printk(KERN_DEBUG "EXT4-fs: someone won our chunk\n"); | |
2092 | */ | |
2093 | ac->ac_b_ex.fe_group = 0; | |
2094 | ac->ac_b_ex.fe_start = 0; | |
2095 | ac->ac_b_ex.fe_len = 0; | |
2096 | ac->ac_status = AC_STATUS_CONTINUE; | |
2097 | ac->ac_flags |= EXT4_MB_HINT_FIRST; | |
2098 | cr = 3; | |
2099 | atomic_inc(&sbi->s_mb_lost_chunks); | |
2100 | goto repeat; | |
2101 | } | |
2102 | } | |
2103 | out: | |
2104 | return err; | |
2105 | } | |
2106 | ||
2107 | #ifdef EXT4_MB_HISTORY | |
2108 | struct ext4_mb_proc_session { | |
2109 | struct ext4_mb_history *history; | |
2110 | struct super_block *sb; | |
2111 | int start; | |
2112 | int max; | |
2113 | }; | |
2114 | ||
2115 | static void *ext4_mb_history_skip_empty(struct ext4_mb_proc_session *s, | |
2116 | struct ext4_mb_history *hs, | |
2117 | int first) | |
2118 | { | |
2119 | if (hs == s->history + s->max) | |
2120 | hs = s->history; | |
2121 | if (!first && hs == s->history + s->start) | |
2122 | return NULL; | |
2123 | while (hs->orig.fe_len == 0) { | |
2124 | hs++; | |
2125 | if (hs == s->history + s->max) | |
2126 | hs = s->history; | |
2127 | if (hs == s->history + s->start) | |
2128 | return NULL; | |
2129 | } | |
2130 | return hs; | |
2131 | } | |
2132 | ||
2133 | static void *ext4_mb_seq_history_start(struct seq_file *seq, loff_t *pos) | |
2134 | { | |
2135 | struct ext4_mb_proc_session *s = seq->private; | |
2136 | struct ext4_mb_history *hs; | |
2137 | int l = *pos; | |
2138 | ||
2139 | if (l == 0) | |
2140 | return SEQ_START_TOKEN; | |
2141 | hs = ext4_mb_history_skip_empty(s, s->history + s->start, 1); | |
2142 | if (!hs) | |
2143 | return NULL; | |
2144 | while (--l && (hs = ext4_mb_history_skip_empty(s, ++hs, 0)) != NULL); | |
2145 | return hs; | |
2146 | } | |
2147 | ||
2148 | static void *ext4_mb_seq_history_next(struct seq_file *seq, void *v, | |
2149 | loff_t *pos) | |
2150 | { | |
2151 | struct ext4_mb_proc_session *s = seq->private; | |
2152 | struct ext4_mb_history *hs = v; | |
2153 | ||
2154 | ++*pos; | |
2155 | if (v == SEQ_START_TOKEN) | |
2156 | return ext4_mb_history_skip_empty(s, s->history + s->start, 1); | |
2157 | else | |
2158 | return ext4_mb_history_skip_empty(s, ++hs, 0); | |
2159 | } | |
2160 | ||
2161 | static int ext4_mb_seq_history_show(struct seq_file *seq, void *v) | |
2162 | { | |
2163 | char buf[25], buf2[25], buf3[25], *fmt; | |
2164 | struct ext4_mb_history *hs = v; | |
2165 | ||
2166 | if (v == SEQ_START_TOKEN) { | |
2167 | seq_printf(seq, "%-5s %-8s %-23s %-23s %-23s %-5s " | |
2168 | "%-5s %-2s %-5s %-5s %-5s %-6s\n", | |
2169 | "pid", "inode", "original", "goal", "result", "found", | |
2170 | "grps", "cr", "flags", "merge", "tail", "broken"); | |
2171 | return 0; | |
2172 | } | |
2173 | ||
2174 | if (hs->op == EXT4_MB_HISTORY_ALLOC) { | |
2175 | fmt = "%-5u %-8u %-23s %-23s %-23s %-5u %-5u %-2u " | |
2176 | "%-5u %-5s %-5u %-6u\n"; | |
2177 | sprintf(buf2, "%lu/%d/%u@%u", hs->result.fe_group, | |
2178 | hs->result.fe_start, hs->result.fe_len, | |
2179 | hs->result.fe_logical); | |
2180 | sprintf(buf, "%lu/%d/%u@%u", hs->orig.fe_group, | |
2181 | hs->orig.fe_start, hs->orig.fe_len, | |
2182 | hs->orig.fe_logical); | |
2183 | sprintf(buf3, "%lu/%d/%u@%u", hs->goal.fe_group, | |
2184 | hs->goal.fe_start, hs->goal.fe_len, | |
2185 | hs->goal.fe_logical); | |
2186 | seq_printf(seq, fmt, hs->pid, hs->ino, buf, buf3, buf2, | |
2187 | hs->found, hs->groups, hs->cr, hs->flags, | |
2188 | hs->merged ? "M" : "", hs->tail, | |
2189 | hs->buddy ? 1 << hs->buddy : 0); | |
2190 | } else if (hs->op == EXT4_MB_HISTORY_PREALLOC) { | |
2191 | fmt = "%-5u %-8u %-23s %-23s %-23s\n"; | |
2192 | sprintf(buf2, "%lu/%d/%u@%u", hs->result.fe_group, | |
2193 | hs->result.fe_start, hs->result.fe_len, | |
2194 | hs->result.fe_logical); | |
2195 | sprintf(buf, "%lu/%d/%u@%u", hs->orig.fe_group, | |
2196 | hs->orig.fe_start, hs->orig.fe_len, | |
2197 | hs->orig.fe_logical); | |
2198 | seq_printf(seq, fmt, hs->pid, hs->ino, buf, "", buf2); | |
2199 | } else if (hs->op == EXT4_MB_HISTORY_DISCARD) { | |
2200 | sprintf(buf2, "%lu/%d/%u", hs->result.fe_group, | |
2201 | hs->result.fe_start, hs->result.fe_len); | |
2202 | seq_printf(seq, "%-5u %-8u %-23s discard\n", | |
2203 | hs->pid, hs->ino, buf2); | |
2204 | } else if (hs->op == EXT4_MB_HISTORY_FREE) { | |
2205 | sprintf(buf2, "%lu/%d/%u", hs->result.fe_group, | |
2206 | hs->result.fe_start, hs->result.fe_len); | |
2207 | seq_printf(seq, "%-5u %-8u %-23s free\n", | |
2208 | hs->pid, hs->ino, buf2); | |
2209 | } | |
2210 | return 0; | |
2211 | } | |
2212 | ||
2213 | static void ext4_mb_seq_history_stop(struct seq_file *seq, void *v) | |
2214 | { | |
2215 | } | |
2216 | ||
2217 | static struct seq_operations ext4_mb_seq_history_ops = { | |
2218 | .start = ext4_mb_seq_history_start, | |
2219 | .next = ext4_mb_seq_history_next, | |
2220 | .stop = ext4_mb_seq_history_stop, | |
2221 | .show = ext4_mb_seq_history_show, | |
2222 | }; | |
2223 | ||
2224 | static int ext4_mb_seq_history_open(struct inode *inode, struct file *file) | |
2225 | { | |
2226 | struct super_block *sb = PDE(inode)->data; | |
2227 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2228 | struct ext4_mb_proc_session *s; | |
2229 | int rc; | |
2230 | int size; | |
2231 | ||
2232 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
2233 | if (s == NULL) | |
2234 | return -ENOMEM; | |
2235 | s->sb = sb; | |
2236 | size = sizeof(struct ext4_mb_history) * sbi->s_mb_history_max; | |
2237 | s->history = kmalloc(size, GFP_KERNEL); | |
2238 | if (s->history == NULL) { | |
2239 | kfree(s); | |
2240 | return -ENOMEM; | |
2241 | } | |
2242 | ||
2243 | spin_lock(&sbi->s_mb_history_lock); | |
2244 | memcpy(s->history, sbi->s_mb_history, size); | |
2245 | s->max = sbi->s_mb_history_max; | |
2246 | s->start = sbi->s_mb_history_cur % s->max; | |
2247 | spin_unlock(&sbi->s_mb_history_lock); | |
2248 | ||
2249 | rc = seq_open(file, &ext4_mb_seq_history_ops); | |
2250 | if (rc == 0) { | |
2251 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2252 | m->private = s; | |
2253 | } else { | |
2254 | kfree(s->history); | |
2255 | kfree(s); | |
2256 | } | |
2257 | return rc; | |
2258 | ||
2259 | } | |
2260 | ||
2261 | static int ext4_mb_seq_history_release(struct inode *inode, struct file *file) | |
2262 | { | |
2263 | struct seq_file *seq = (struct seq_file *)file->private_data; | |
2264 | struct ext4_mb_proc_session *s = seq->private; | |
2265 | kfree(s->history); | |
2266 | kfree(s); | |
2267 | return seq_release(inode, file); | |
2268 | } | |
2269 | ||
2270 | static ssize_t ext4_mb_seq_history_write(struct file *file, | |
2271 | const char __user *buffer, | |
2272 | size_t count, loff_t *ppos) | |
2273 | { | |
2274 | struct seq_file *seq = (struct seq_file *)file->private_data; | |
2275 | struct ext4_mb_proc_session *s = seq->private; | |
2276 | struct super_block *sb = s->sb; | |
2277 | char str[32]; | |
2278 | int value; | |
2279 | ||
2280 | if (count >= sizeof(str)) { | |
2281 | printk(KERN_ERR "EXT4-fs: %s string too long, max %u bytes\n", | |
2282 | "mb_history", (int)sizeof(str)); | |
2283 | return -EOVERFLOW; | |
2284 | } | |
2285 | ||
2286 | if (copy_from_user(str, buffer, count)) | |
2287 | return -EFAULT; | |
2288 | ||
2289 | value = simple_strtol(str, NULL, 0); | |
2290 | if (value < 0) | |
2291 | return -ERANGE; | |
2292 | EXT4_SB(sb)->s_mb_history_filter = value; | |
2293 | ||
2294 | return count; | |
2295 | } | |
2296 | ||
2297 | static struct file_operations ext4_mb_seq_history_fops = { | |
2298 | .owner = THIS_MODULE, | |
2299 | .open = ext4_mb_seq_history_open, | |
2300 | .read = seq_read, | |
2301 | .write = ext4_mb_seq_history_write, | |
2302 | .llseek = seq_lseek, | |
2303 | .release = ext4_mb_seq_history_release, | |
2304 | }; | |
2305 | ||
2306 | static void *ext4_mb_seq_groups_start(struct seq_file *seq, loff_t *pos) | |
2307 | { | |
2308 | struct super_block *sb = seq->private; | |
2309 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2310 | ext4_group_t group; | |
2311 | ||
2312 | if (*pos < 0 || *pos >= sbi->s_groups_count) | |
2313 | return NULL; | |
2314 | ||
2315 | group = *pos + 1; | |
2316 | return (void *) group; | |
2317 | } | |
2318 | ||
2319 | static void *ext4_mb_seq_groups_next(struct seq_file *seq, void *v, loff_t *pos) | |
2320 | { | |
2321 | struct super_block *sb = seq->private; | |
2322 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2323 | ext4_group_t group; | |
2324 | ||
2325 | ++*pos; | |
2326 | if (*pos < 0 || *pos >= sbi->s_groups_count) | |
2327 | return NULL; | |
2328 | group = *pos + 1; | |
2329 | return (void *) group;; | |
2330 | } | |
2331 | ||
2332 | static int ext4_mb_seq_groups_show(struct seq_file *seq, void *v) | |
2333 | { | |
2334 | struct super_block *sb = seq->private; | |
2335 | long group = (long) v; | |
2336 | int i; | |
2337 | int err; | |
2338 | struct ext4_buddy e4b; | |
2339 | struct sg { | |
2340 | struct ext4_group_info info; | |
2341 | unsigned short counters[16]; | |
2342 | } sg; | |
2343 | ||
2344 | group--; | |
2345 | if (group == 0) | |
2346 | seq_printf(seq, "#%-5s: %-5s %-5s %-5s " | |
2347 | "[ %-5s %-5s %-5s %-5s %-5s %-5s %-5s " | |
2348 | "%-5s %-5s %-5s %-5s %-5s %-5s %-5s ]\n", | |
2349 | "group", "free", "frags", "first", | |
2350 | "2^0", "2^1", "2^2", "2^3", "2^4", "2^5", "2^6", | |
2351 | "2^7", "2^8", "2^9", "2^10", "2^11", "2^12", "2^13"); | |
2352 | ||
2353 | i = (sb->s_blocksize_bits + 2) * sizeof(sg.info.bb_counters[0]) + | |
2354 | sizeof(struct ext4_group_info); | |
2355 | err = ext4_mb_load_buddy(sb, group, &e4b); | |
2356 | if (err) { | |
2357 | seq_printf(seq, "#%-5lu: I/O error\n", group); | |
2358 | return 0; | |
2359 | } | |
2360 | ext4_lock_group(sb, group); | |
2361 | memcpy(&sg, ext4_get_group_info(sb, group), i); | |
2362 | ext4_unlock_group(sb, group); | |
2363 | ext4_mb_release_desc(&e4b); | |
2364 | ||
2365 | seq_printf(seq, "#%-5lu: %-5u %-5u %-5u [", group, sg.info.bb_free, | |
2366 | sg.info.bb_fragments, sg.info.bb_first_free); | |
2367 | for (i = 0; i <= 13; i++) | |
2368 | seq_printf(seq, " %-5u", i <= sb->s_blocksize_bits + 1 ? | |
2369 | sg.info.bb_counters[i] : 0); | |
2370 | seq_printf(seq, " ]\n"); | |
2371 | ||
2372 | return 0; | |
2373 | } | |
2374 | ||
2375 | static void ext4_mb_seq_groups_stop(struct seq_file *seq, void *v) | |
2376 | { | |
2377 | } | |
2378 | ||
2379 | static struct seq_operations ext4_mb_seq_groups_ops = { | |
2380 | .start = ext4_mb_seq_groups_start, | |
2381 | .next = ext4_mb_seq_groups_next, | |
2382 | .stop = ext4_mb_seq_groups_stop, | |
2383 | .show = ext4_mb_seq_groups_show, | |
2384 | }; | |
2385 | ||
2386 | static int ext4_mb_seq_groups_open(struct inode *inode, struct file *file) | |
2387 | { | |
2388 | struct super_block *sb = PDE(inode)->data; | |
2389 | int rc; | |
2390 | ||
2391 | rc = seq_open(file, &ext4_mb_seq_groups_ops); | |
2392 | if (rc == 0) { | |
2393 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2394 | m->private = sb; | |
2395 | } | |
2396 | return rc; | |
2397 | ||
2398 | } | |
2399 | ||
2400 | static struct file_operations ext4_mb_seq_groups_fops = { | |
2401 | .owner = THIS_MODULE, | |
2402 | .open = ext4_mb_seq_groups_open, | |
2403 | .read = seq_read, | |
2404 | .llseek = seq_lseek, | |
2405 | .release = seq_release, | |
2406 | }; | |
2407 | ||
2408 | static void ext4_mb_history_release(struct super_block *sb) | |
2409 | { | |
2410 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2411 | ||
2412 | remove_proc_entry("mb_groups", sbi->s_mb_proc); | |
2413 | remove_proc_entry("mb_history", sbi->s_mb_proc); | |
2414 | ||
2415 | kfree(sbi->s_mb_history); | |
2416 | } | |
2417 | ||
2418 | static void ext4_mb_history_init(struct super_block *sb) | |
2419 | { | |
2420 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2421 | int i; | |
2422 | ||
2423 | if (sbi->s_mb_proc != NULL) { | |
2424 | struct proc_dir_entry *p; | |
2425 | p = create_proc_entry("mb_history", S_IRUGO, sbi->s_mb_proc); | |
2426 | if (p) { | |
2427 | p->proc_fops = &ext4_mb_seq_history_fops; | |
2428 | p->data = sb; | |
2429 | } | |
2430 | p = create_proc_entry("mb_groups", S_IRUGO, sbi->s_mb_proc); | |
2431 | if (p) { | |
2432 | p->proc_fops = &ext4_mb_seq_groups_fops; | |
2433 | p->data = sb; | |
2434 | } | |
2435 | } | |
2436 | ||
2437 | sbi->s_mb_history_max = 1000; | |
2438 | sbi->s_mb_history_cur = 0; | |
2439 | spin_lock_init(&sbi->s_mb_history_lock); | |
2440 | i = sbi->s_mb_history_max * sizeof(struct ext4_mb_history); | |
2441 | sbi->s_mb_history = kmalloc(i, GFP_KERNEL); | |
2442 | if (likely(sbi->s_mb_history != NULL)) | |
2443 | memset(sbi->s_mb_history, 0, i); | |
2444 | /* if we can't allocate history, then we simple won't use it */ | |
2445 | } | |
2446 | ||
2447 | static void ext4_mb_store_history(struct ext4_allocation_context *ac) | |
2448 | { | |
2449 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
2450 | struct ext4_mb_history h; | |
2451 | ||
2452 | if (unlikely(sbi->s_mb_history == NULL)) | |
2453 | return; | |
2454 | ||
2455 | if (!(ac->ac_op & sbi->s_mb_history_filter)) | |
2456 | return; | |
2457 | ||
2458 | h.op = ac->ac_op; | |
2459 | h.pid = current->pid; | |
2460 | h.ino = ac->ac_inode ? ac->ac_inode->i_ino : 0; | |
2461 | h.orig = ac->ac_o_ex; | |
2462 | h.result = ac->ac_b_ex; | |
2463 | h.flags = ac->ac_flags; | |
2464 | h.found = ac->ac_found; | |
2465 | h.groups = ac->ac_groups_scanned; | |
2466 | h.cr = ac->ac_criteria; | |
2467 | h.tail = ac->ac_tail; | |
2468 | h.buddy = ac->ac_buddy; | |
2469 | h.merged = 0; | |
2470 | if (ac->ac_op == EXT4_MB_HISTORY_ALLOC) { | |
2471 | if (ac->ac_g_ex.fe_start == ac->ac_b_ex.fe_start && | |
2472 | ac->ac_g_ex.fe_group == ac->ac_b_ex.fe_group) | |
2473 | h.merged = 1; | |
2474 | h.goal = ac->ac_g_ex; | |
2475 | h.result = ac->ac_f_ex; | |
2476 | } | |
2477 | ||
2478 | spin_lock(&sbi->s_mb_history_lock); | |
2479 | memcpy(sbi->s_mb_history + sbi->s_mb_history_cur, &h, sizeof(h)); | |
2480 | if (++sbi->s_mb_history_cur >= sbi->s_mb_history_max) | |
2481 | sbi->s_mb_history_cur = 0; | |
2482 | spin_unlock(&sbi->s_mb_history_lock); | |
2483 | } | |
2484 | ||
2485 | #else | |
2486 | #define ext4_mb_history_release(sb) | |
2487 | #define ext4_mb_history_init(sb) | |
2488 | #endif | |
2489 | ||
2490 | static int ext4_mb_init_backend(struct super_block *sb) | |
2491 | { | |
2492 | ext4_group_t i; | |
2493 | int j, len, metalen; | |
2494 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2495 | int num_meta_group_infos = | |
2496 | (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) >> | |
2497 | EXT4_DESC_PER_BLOCK_BITS(sb); | |
2498 | struct ext4_group_info **meta_group_info; | |
2499 | ||
2500 | /* An 8TB filesystem with 64-bit pointers requires a 4096 byte | |
2501 | * kmalloc. A 128kb malloc should suffice for a 256TB filesystem. | |
2502 | * So a two level scheme suffices for now. */ | |
2503 | sbi->s_group_info = kmalloc(sizeof(*sbi->s_group_info) * | |
2504 | num_meta_group_infos, GFP_KERNEL); | |
2505 | if (sbi->s_group_info == NULL) { | |
2506 | printk(KERN_ERR "EXT4-fs: can't allocate buddy meta group\n"); | |
2507 | return -ENOMEM; | |
2508 | } | |
2509 | sbi->s_buddy_cache = new_inode(sb); | |
2510 | if (sbi->s_buddy_cache == NULL) { | |
2511 | printk(KERN_ERR "EXT4-fs: can't get new inode\n"); | |
2512 | goto err_freesgi; | |
2513 | } | |
2514 | EXT4_I(sbi->s_buddy_cache)->i_disksize = 0; | |
2515 | ||
2516 | metalen = sizeof(*meta_group_info) << EXT4_DESC_PER_BLOCK_BITS(sb); | |
2517 | for (i = 0; i < num_meta_group_infos; i++) { | |
2518 | if ((i + 1) == num_meta_group_infos) | |
2519 | metalen = sizeof(*meta_group_info) * | |
2520 | (sbi->s_groups_count - | |
2521 | (i << EXT4_DESC_PER_BLOCK_BITS(sb))); | |
2522 | meta_group_info = kmalloc(metalen, GFP_KERNEL); | |
2523 | if (meta_group_info == NULL) { | |
2524 | printk(KERN_ERR "EXT4-fs: can't allocate mem for a " | |
2525 | "buddy group\n"); | |
2526 | goto err_freemeta; | |
2527 | } | |
2528 | sbi->s_group_info[i] = meta_group_info; | |
2529 | } | |
2530 | ||
2531 | /* | |
2532 | * calculate needed size. if change bb_counters size, | |
2533 | * don't forget about ext4_mb_generate_buddy() | |
2534 | */ | |
2535 | len = sizeof(struct ext4_group_info); | |
2536 | len += sizeof(unsigned short) * (sb->s_blocksize_bits + 2); | |
2537 | for (i = 0; i < sbi->s_groups_count; i++) { | |
2538 | struct ext4_group_desc *desc; | |
2539 | ||
2540 | meta_group_info = | |
2541 | sbi->s_group_info[i >> EXT4_DESC_PER_BLOCK_BITS(sb)]; | |
2542 | j = i & (EXT4_DESC_PER_BLOCK(sb) - 1); | |
2543 | ||
2544 | meta_group_info[j] = kzalloc(len, GFP_KERNEL); | |
2545 | if (meta_group_info[j] == NULL) { | |
2546 | printk(KERN_ERR "EXT4-fs: can't allocate buddy mem\n"); | |
2547 | i--; | |
2548 | goto err_freebuddy; | |
2549 | } | |
2550 | desc = ext4_get_group_desc(sb, i, NULL); | |
2551 | if (desc == NULL) { | |
2552 | printk(KERN_ERR | |
2553 | "EXT4-fs: can't read descriptor %lu\n", i); | |
2554 | goto err_freebuddy; | |
2555 | } | |
2556 | memset(meta_group_info[j], 0, len); | |
2557 | set_bit(EXT4_GROUP_INFO_NEED_INIT_BIT, | |
2558 | &(meta_group_info[j]->bb_state)); | |
2559 | ||
2560 | /* | |
2561 | * initialize bb_free to be able to skip | |
2562 | * empty groups without initialization | |
2563 | */ | |
2564 | if (desc->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { | |
2565 | meta_group_info[j]->bb_free = | |
2566 | ext4_free_blocks_after_init(sb, i, desc); | |
2567 | } else { | |
2568 | meta_group_info[j]->bb_free = | |
2569 | le16_to_cpu(desc->bg_free_blocks_count); | |
2570 | } | |
2571 | ||
2572 | INIT_LIST_HEAD(&meta_group_info[j]->bb_prealloc_list); | |
2573 | ||
2574 | #ifdef DOUBLE_CHECK | |
2575 | { | |
2576 | struct buffer_head *bh; | |
2577 | meta_group_info[j]->bb_bitmap = | |
2578 | kmalloc(sb->s_blocksize, GFP_KERNEL); | |
2579 | BUG_ON(meta_group_info[j]->bb_bitmap == NULL); | |
2580 | bh = read_block_bitmap(sb, i); | |
2581 | BUG_ON(bh == NULL); | |
2582 | memcpy(meta_group_info[j]->bb_bitmap, bh->b_data, | |
2583 | sb->s_blocksize); | |
2584 | put_bh(bh); | |
2585 | } | |
2586 | #endif | |
2587 | ||
2588 | } | |
2589 | ||
2590 | return 0; | |
2591 | ||
2592 | err_freebuddy: | |
2593 | while (i >= 0) { | |
2594 | kfree(ext4_get_group_info(sb, i)); | |
2595 | i--; | |
2596 | } | |
2597 | i = num_meta_group_infos; | |
2598 | err_freemeta: | |
2599 | while (--i >= 0) | |
2600 | kfree(sbi->s_group_info[i]); | |
2601 | iput(sbi->s_buddy_cache); | |
2602 | err_freesgi: | |
2603 | kfree(sbi->s_group_info); | |
2604 | return -ENOMEM; | |
2605 | } | |
2606 | ||
2607 | int ext4_mb_init(struct super_block *sb, int needs_recovery) | |
2608 | { | |
2609 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2610 | unsigned i; | |
2611 | unsigned offset; | |
2612 | unsigned max; | |
2613 | ||
2614 | if (!test_opt(sb, MBALLOC)) | |
2615 | return 0; | |
2616 | ||
2617 | i = (sb->s_blocksize_bits + 2) * sizeof(unsigned short); | |
2618 | ||
2619 | sbi->s_mb_offsets = kmalloc(i, GFP_KERNEL); | |
2620 | if (sbi->s_mb_offsets == NULL) { | |
2621 | clear_opt(sbi->s_mount_opt, MBALLOC); | |
2622 | return -ENOMEM; | |
2623 | } | |
2624 | sbi->s_mb_maxs = kmalloc(i, GFP_KERNEL); | |
2625 | if (sbi->s_mb_maxs == NULL) { | |
2626 | clear_opt(sbi->s_mount_opt, MBALLOC); | |
2627 | kfree(sbi->s_mb_maxs); | |
2628 | return -ENOMEM; | |
2629 | } | |
2630 | ||
2631 | /* order 0 is regular bitmap */ | |
2632 | sbi->s_mb_maxs[0] = sb->s_blocksize << 3; | |
2633 | sbi->s_mb_offsets[0] = 0; | |
2634 | ||
2635 | i = 1; | |
2636 | offset = 0; | |
2637 | max = sb->s_blocksize << 2; | |
2638 | do { | |
2639 | sbi->s_mb_offsets[i] = offset; | |
2640 | sbi->s_mb_maxs[i] = max; | |
2641 | offset += 1 << (sb->s_blocksize_bits - i); | |
2642 | max = max >> 1; | |
2643 | i++; | |
2644 | } while (i <= sb->s_blocksize_bits + 1); | |
2645 | ||
2646 | /* init file for buddy data */ | |
2647 | i = ext4_mb_init_backend(sb); | |
2648 | if (i) { | |
2649 | clear_opt(sbi->s_mount_opt, MBALLOC); | |
2650 | kfree(sbi->s_mb_offsets); | |
2651 | kfree(sbi->s_mb_maxs); | |
2652 | return i; | |
2653 | } | |
2654 | ||
2655 | spin_lock_init(&sbi->s_md_lock); | |
2656 | INIT_LIST_HEAD(&sbi->s_active_transaction); | |
2657 | INIT_LIST_HEAD(&sbi->s_closed_transaction); | |
2658 | INIT_LIST_HEAD(&sbi->s_committed_transaction); | |
2659 | spin_lock_init(&sbi->s_bal_lock); | |
2660 | ||
2661 | sbi->s_mb_max_to_scan = MB_DEFAULT_MAX_TO_SCAN; | |
2662 | sbi->s_mb_min_to_scan = MB_DEFAULT_MIN_TO_SCAN; | |
2663 | sbi->s_mb_stats = MB_DEFAULT_STATS; | |
2664 | sbi->s_mb_stream_request = MB_DEFAULT_STREAM_THRESHOLD; | |
2665 | sbi->s_mb_order2_reqs = MB_DEFAULT_ORDER2_REQS; | |
2666 | sbi->s_mb_history_filter = EXT4_MB_HISTORY_DEFAULT; | |
2667 | sbi->s_mb_group_prealloc = MB_DEFAULT_GROUP_PREALLOC; | |
2668 | ||
2669 | i = sizeof(struct ext4_locality_group) * NR_CPUS; | |
2670 | sbi->s_locality_groups = kmalloc(i, GFP_KERNEL); | |
2671 | if (sbi->s_locality_groups == NULL) { | |
2672 | clear_opt(sbi->s_mount_opt, MBALLOC); | |
2673 | kfree(sbi->s_mb_offsets); | |
2674 | kfree(sbi->s_mb_maxs); | |
2675 | return -ENOMEM; | |
2676 | } | |
2677 | for (i = 0; i < NR_CPUS; i++) { | |
2678 | struct ext4_locality_group *lg; | |
2679 | lg = &sbi->s_locality_groups[i]; | |
2680 | mutex_init(&lg->lg_mutex); | |
2681 | INIT_LIST_HEAD(&lg->lg_prealloc_list); | |
2682 | spin_lock_init(&lg->lg_prealloc_lock); | |
2683 | } | |
2684 | ||
2685 | ext4_mb_init_per_dev_proc(sb); | |
2686 | ext4_mb_history_init(sb); | |
2687 | ||
2688 | printk("EXT4-fs: mballoc enabled\n"); | |
2689 | return 0; | |
2690 | } | |
2691 | ||
2692 | /* need to called with ext4 group lock (ext4_lock_group) */ | |
2693 | static void ext4_mb_cleanup_pa(struct ext4_group_info *grp) | |
2694 | { | |
2695 | struct ext4_prealloc_space *pa; | |
2696 | struct list_head *cur, *tmp; | |
2697 | int count = 0; | |
2698 | ||
2699 | list_for_each_safe(cur, tmp, &grp->bb_prealloc_list) { | |
2700 | pa = list_entry(cur, struct ext4_prealloc_space, pa_group_list); | |
2701 | list_del(&pa->pa_group_list); | |
2702 | count++; | |
2703 | kfree(pa); | |
2704 | } | |
2705 | if (count) | |
2706 | mb_debug("mballoc: %u PAs left\n", count); | |
2707 | ||
2708 | } | |
2709 | ||
2710 | int ext4_mb_release(struct super_block *sb) | |
2711 | { | |
2712 | ext4_group_t i; | |
2713 | int num_meta_group_infos; | |
2714 | struct ext4_group_info *grinfo; | |
2715 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2716 | ||
2717 | if (!test_opt(sb, MBALLOC)) | |
2718 | return 0; | |
2719 | ||
2720 | /* release freed, non-committed blocks */ | |
2721 | spin_lock(&sbi->s_md_lock); | |
2722 | list_splice_init(&sbi->s_closed_transaction, | |
2723 | &sbi->s_committed_transaction); | |
2724 | list_splice_init(&sbi->s_active_transaction, | |
2725 | &sbi->s_committed_transaction); | |
2726 | spin_unlock(&sbi->s_md_lock); | |
2727 | ext4_mb_free_committed_blocks(sb); | |
2728 | ||
2729 | if (sbi->s_group_info) { | |
2730 | for (i = 0; i < sbi->s_groups_count; i++) { | |
2731 | grinfo = ext4_get_group_info(sb, i); | |
2732 | #ifdef DOUBLE_CHECK | |
2733 | kfree(grinfo->bb_bitmap); | |
2734 | #endif | |
2735 | ext4_lock_group(sb, i); | |
2736 | ext4_mb_cleanup_pa(grinfo); | |
2737 | ext4_unlock_group(sb, i); | |
2738 | kfree(grinfo); | |
2739 | } | |
2740 | num_meta_group_infos = (sbi->s_groups_count + | |
2741 | EXT4_DESC_PER_BLOCK(sb) - 1) >> | |
2742 | EXT4_DESC_PER_BLOCK_BITS(sb); | |
2743 | for (i = 0; i < num_meta_group_infos; i++) | |
2744 | kfree(sbi->s_group_info[i]); | |
2745 | kfree(sbi->s_group_info); | |
2746 | } | |
2747 | kfree(sbi->s_mb_offsets); | |
2748 | kfree(sbi->s_mb_maxs); | |
2749 | if (sbi->s_buddy_cache) | |
2750 | iput(sbi->s_buddy_cache); | |
2751 | if (sbi->s_mb_stats) { | |
2752 | printk(KERN_INFO | |
2753 | "EXT4-fs: mballoc: %u blocks %u reqs (%u success)\n", | |
2754 | atomic_read(&sbi->s_bal_allocated), | |
2755 | atomic_read(&sbi->s_bal_reqs), | |
2756 | atomic_read(&sbi->s_bal_success)); | |
2757 | printk(KERN_INFO | |
2758 | "EXT4-fs: mballoc: %u extents scanned, %u goal hits, " | |
2759 | "%u 2^N hits, %u breaks, %u lost\n", | |
2760 | atomic_read(&sbi->s_bal_ex_scanned), | |
2761 | atomic_read(&sbi->s_bal_goals), | |
2762 | atomic_read(&sbi->s_bal_2orders), | |
2763 | atomic_read(&sbi->s_bal_breaks), | |
2764 | atomic_read(&sbi->s_mb_lost_chunks)); | |
2765 | printk(KERN_INFO | |
2766 | "EXT4-fs: mballoc: %lu generated and it took %Lu\n", | |
2767 | sbi->s_mb_buddies_generated++, | |
2768 | sbi->s_mb_generation_time); | |
2769 | printk(KERN_INFO | |
2770 | "EXT4-fs: mballoc: %u preallocated, %u discarded\n", | |
2771 | atomic_read(&sbi->s_mb_preallocated), | |
2772 | atomic_read(&sbi->s_mb_discarded)); | |
2773 | } | |
2774 | ||
2775 | kfree(sbi->s_locality_groups); | |
2776 | ||
2777 | ext4_mb_history_release(sb); | |
2778 | ext4_mb_destroy_per_dev_proc(sb); | |
2779 | ||
2780 | return 0; | |
2781 | } | |
2782 | ||
2783 | static void ext4_mb_free_committed_blocks(struct super_block *sb) | |
2784 | { | |
2785 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2786 | int err; | |
2787 | int i; | |
2788 | int count = 0; | |
2789 | int count2 = 0; | |
2790 | struct ext4_free_metadata *md; | |
2791 | struct ext4_buddy e4b; | |
2792 | ||
2793 | if (list_empty(&sbi->s_committed_transaction)) | |
2794 | return; | |
2795 | ||
2796 | /* there is committed blocks to be freed yet */ | |
2797 | do { | |
2798 | /* get next array of blocks */ | |
2799 | md = NULL; | |
2800 | spin_lock(&sbi->s_md_lock); | |
2801 | if (!list_empty(&sbi->s_committed_transaction)) { | |
2802 | md = list_entry(sbi->s_committed_transaction.next, | |
2803 | struct ext4_free_metadata, list); | |
2804 | list_del(&md->list); | |
2805 | } | |
2806 | spin_unlock(&sbi->s_md_lock); | |
2807 | ||
2808 | if (md == NULL) | |
2809 | break; | |
2810 | ||
2811 | mb_debug("gonna free %u blocks in group %lu (0x%p):", | |
2812 | md->num, md->group, md); | |
2813 | ||
2814 | err = ext4_mb_load_buddy(sb, md->group, &e4b); | |
2815 | /* we expect to find existing buddy because it's pinned */ | |
2816 | BUG_ON(err != 0); | |
2817 | ||
2818 | /* there are blocks to put in buddy to make them really free */ | |
2819 | count += md->num; | |
2820 | count2++; | |
2821 | ext4_lock_group(sb, md->group); | |
2822 | for (i = 0; i < md->num; i++) { | |
2823 | mb_debug(" %u", md->blocks[i]); | |
2824 | err = mb_free_blocks(NULL, &e4b, md->blocks[i], 1); | |
2825 | BUG_ON(err != 0); | |
2826 | } | |
2827 | mb_debug("\n"); | |
2828 | ext4_unlock_group(sb, md->group); | |
2829 | ||
2830 | /* balance refcounts from ext4_mb_free_metadata() */ | |
2831 | page_cache_release(e4b.bd_buddy_page); | |
2832 | page_cache_release(e4b.bd_bitmap_page); | |
2833 | ||
2834 | kfree(md); | |
2835 | ext4_mb_release_desc(&e4b); | |
2836 | ||
2837 | } while (md); | |
2838 | ||
2839 | mb_debug("freed %u blocks in %u structures\n", count, count2); | |
2840 | } | |
2841 | ||
2842 | #define EXT4_ROOT "ext4" | |
2843 | #define EXT4_MB_STATS_NAME "stats" | |
2844 | #define EXT4_MB_MAX_TO_SCAN_NAME "max_to_scan" | |
2845 | #define EXT4_MB_MIN_TO_SCAN_NAME "min_to_scan" | |
2846 | #define EXT4_MB_ORDER2_REQ "order2_req" | |
2847 | #define EXT4_MB_STREAM_REQ "stream_req" | |
2848 | #define EXT4_MB_GROUP_PREALLOC "group_prealloc" | |
2849 | ||
2850 | ||
2851 | ||
2852 | #define MB_PROC_VALUE_READ(name) \ | |
2853 | static int ext4_mb_read_##name(char *page, char **start, \ | |
2854 | off_t off, int count, int *eof, void *data) \ | |
2855 | { \ | |
2856 | struct ext4_sb_info *sbi = data; \ | |
2857 | int len; \ | |
2858 | *eof = 1; \ | |
2859 | if (off != 0) \ | |
2860 | return 0; \ | |
2861 | len = sprintf(page, "%ld\n", sbi->s_mb_##name); \ | |
2862 | *start = page; \ | |
2863 | return len; \ | |
2864 | } | |
2865 | ||
2866 | #define MB_PROC_VALUE_WRITE(name) \ | |
2867 | static int ext4_mb_write_##name(struct file *file, \ | |
2868 | const char __user *buf, unsigned long cnt, void *data) \ | |
2869 | { \ | |
2870 | struct ext4_sb_info *sbi = data; \ | |
2871 | char str[32]; \ | |
2872 | long value; \ | |
2873 | if (cnt >= sizeof(str)) \ | |
2874 | return -EINVAL; \ | |
2875 | if (copy_from_user(str, buf, cnt)) \ | |
2876 | return -EFAULT; \ | |
2877 | value = simple_strtol(str, NULL, 0); \ | |
2878 | if (value <= 0) \ | |
2879 | return -ERANGE; \ | |
2880 | sbi->s_mb_##name = value; \ | |
2881 | return cnt; \ | |
2882 | } | |
2883 | ||
2884 | MB_PROC_VALUE_READ(stats); | |
2885 | MB_PROC_VALUE_WRITE(stats); | |
2886 | MB_PROC_VALUE_READ(max_to_scan); | |
2887 | MB_PROC_VALUE_WRITE(max_to_scan); | |
2888 | MB_PROC_VALUE_READ(min_to_scan); | |
2889 | MB_PROC_VALUE_WRITE(min_to_scan); | |
2890 | MB_PROC_VALUE_READ(order2_reqs); | |
2891 | MB_PROC_VALUE_WRITE(order2_reqs); | |
2892 | MB_PROC_VALUE_READ(stream_request); | |
2893 | MB_PROC_VALUE_WRITE(stream_request); | |
2894 | MB_PROC_VALUE_READ(group_prealloc); | |
2895 | MB_PROC_VALUE_WRITE(group_prealloc); | |
2896 | ||
2897 | #define MB_PROC_HANDLER(name, var) \ | |
2898 | do { \ | |
2899 | proc = create_proc_entry(name, mode, sbi->s_mb_proc); \ | |
2900 | if (proc == NULL) { \ | |
2901 | printk(KERN_ERR "EXT4-fs: can't to create %s\n", name); \ | |
2902 | goto err_out; \ | |
2903 | } \ | |
2904 | proc->data = sbi; \ | |
2905 | proc->read_proc = ext4_mb_read_##var ; \ | |
2906 | proc->write_proc = ext4_mb_write_##var; \ | |
2907 | } while (0) | |
2908 | ||
2909 | static int ext4_mb_init_per_dev_proc(struct super_block *sb) | |
2910 | { | |
2911 | mode_t mode = S_IFREG | S_IRUGO | S_IWUSR; | |
2912 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2913 | struct proc_dir_entry *proc; | |
2914 | char devname[64]; | |
2915 | ||
2916 | snprintf(devname, sizeof(devname) - 1, "%s", | |
2917 | bdevname(sb->s_bdev, devname)); | |
2918 | sbi->s_mb_proc = proc_mkdir(devname, proc_root_ext4); | |
2919 | ||
2920 | MB_PROC_HANDLER(EXT4_MB_STATS_NAME, stats); | |
2921 | MB_PROC_HANDLER(EXT4_MB_MAX_TO_SCAN_NAME, max_to_scan); | |
2922 | MB_PROC_HANDLER(EXT4_MB_MIN_TO_SCAN_NAME, min_to_scan); | |
2923 | MB_PROC_HANDLER(EXT4_MB_ORDER2_REQ, order2_reqs); | |
2924 | MB_PROC_HANDLER(EXT4_MB_STREAM_REQ, stream_request); | |
2925 | MB_PROC_HANDLER(EXT4_MB_GROUP_PREALLOC, group_prealloc); | |
2926 | ||
2927 | return 0; | |
2928 | ||
2929 | err_out: | |
2930 | printk(KERN_ERR "EXT4-fs: Unable to create %s\n", devname); | |
2931 | remove_proc_entry(EXT4_MB_GROUP_PREALLOC, sbi->s_mb_proc); | |
2932 | remove_proc_entry(EXT4_MB_STREAM_REQ, sbi->s_mb_proc); | |
2933 | remove_proc_entry(EXT4_MB_ORDER2_REQ, sbi->s_mb_proc); | |
2934 | remove_proc_entry(EXT4_MB_MIN_TO_SCAN_NAME, sbi->s_mb_proc); | |
2935 | remove_proc_entry(EXT4_MB_MAX_TO_SCAN_NAME, sbi->s_mb_proc); | |
2936 | remove_proc_entry(EXT4_MB_STATS_NAME, sbi->s_mb_proc); | |
2937 | remove_proc_entry(devname, proc_root_ext4); | |
2938 | sbi->s_mb_proc = NULL; | |
2939 | ||
2940 | return -ENOMEM; | |
2941 | } | |
2942 | ||
2943 | static int ext4_mb_destroy_per_dev_proc(struct super_block *sb) | |
2944 | { | |
2945 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
2946 | char devname[64]; | |
2947 | ||
2948 | if (sbi->s_mb_proc == NULL) | |
2949 | return -EINVAL; | |
2950 | ||
2951 | snprintf(devname, sizeof(devname) - 1, "%s", | |
2952 | bdevname(sb->s_bdev, devname)); | |
2953 | remove_proc_entry(EXT4_MB_GROUP_PREALLOC, sbi->s_mb_proc); | |
2954 | remove_proc_entry(EXT4_MB_STREAM_REQ, sbi->s_mb_proc); | |
2955 | remove_proc_entry(EXT4_MB_ORDER2_REQ, sbi->s_mb_proc); | |
2956 | remove_proc_entry(EXT4_MB_MIN_TO_SCAN_NAME, sbi->s_mb_proc); | |
2957 | remove_proc_entry(EXT4_MB_MAX_TO_SCAN_NAME, sbi->s_mb_proc); | |
2958 | remove_proc_entry(EXT4_MB_STATS_NAME, sbi->s_mb_proc); | |
2959 | remove_proc_entry(devname, proc_root_ext4); | |
2960 | ||
2961 | return 0; | |
2962 | } | |
2963 | ||
2964 | int __init init_ext4_mballoc(void) | |
2965 | { | |
2966 | ext4_pspace_cachep = | |
2967 | kmem_cache_create("ext4_prealloc_space", | |
2968 | sizeof(struct ext4_prealloc_space), | |
2969 | 0, SLAB_RECLAIM_ACCOUNT, NULL); | |
2970 | if (ext4_pspace_cachep == NULL) | |
2971 | return -ENOMEM; | |
2972 | ||
256bdb49 ES |
2973 | ext4_ac_cachep = |
2974 | kmem_cache_create("ext4_alloc_context", | |
2975 | sizeof(struct ext4_allocation_context), | |
2976 | 0, SLAB_RECLAIM_ACCOUNT, NULL); | |
2977 | if (ext4_ac_cachep == NULL) { | |
2978 | kmem_cache_destroy(ext4_pspace_cachep); | |
2979 | return -ENOMEM; | |
2980 | } | |
c9de560d AT |
2981 | #ifdef CONFIG_PROC_FS |
2982 | proc_root_ext4 = proc_mkdir(EXT4_ROOT, proc_root_fs); | |
2983 | if (proc_root_ext4 == NULL) | |
2984 | printk(KERN_ERR "EXT4-fs: Unable to create %s\n", EXT4_ROOT); | |
2985 | #endif | |
c9de560d AT |
2986 | return 0; |
2987 | } | |
2988 | ||
2989 | void exit_ext4_mballoc(void) | |
2990 | { | |
2991 | /* XXX: synchronize_rcu(); */ | |
2992 | kmem_cache_destroy(ext4_pspace_cachep); | |
256bdb49 | 2993 | kmem_cache_destroy(ext4_ac_cachep); |
c9de560d AT |
2994 | #ifdef CONFIG_PROC_FS |
2995 | remove_proc_entry(EXT4_ROOT, proc_root_fs); | |
2996 | #endif | |
2997 | } | |
2998 | ||
2999 | ||
3000 | /* | |
3001 | * Check quota and mark choosed space (ac->ac_b_ex) non-free in bitmaps | |
3002 | * Returns 0 if success or error code | |
3003 | */ | |
3004 | static int ext4_mb_mark_diskspace_used(struct ext4_allocation_context *ac, | |
3005 | handle_t *handle) | |
3006 | { | |
3007 | struct buffer_head *bitmap_bh = NULL; | |
3008 | struct ext4_super_block *es; | |
3009 | struct ext4_group_desc *gdp; | |
3010 | struct buffer_head *gdp_bh; | |
3011 | struct ext4_sb_info *sbi; | |
3012 | struct super_block *sb; | |
3013 | ext4_fsblk_t block; | |
3014 | int err; | |
3015 | ||
3016 | BUG_ON(ac->ac_status != AC_STATUS_FOUND); | |
3017 | BUG_ON(ac->ac_b_ex.fe_len <= 0); | |
3018 | ||
3019 | sb = ac->ac_sb; | |
3020 | sbi = EXT4_SB(sb); | |
3021 | es = sbi->s_es; | |
3022 | ||
3023 | ext4_debug("using block group %lu(%d)\n", ac->ac_b_ex.fe_group, | |
3024 | gdp->bg_free_blocks_count); | |
3025 | ||
3026 | err = -EIO; | |
3027 | bitmap_bh = read_block_bitmap(sb, ac->ac_b_ex.fe_group); | |
3028 | if (!bitmap_bh) | |
3029 | goto out_err; | |
3030 | ||
3031 | err = ext4_journal_get_write_access(handle, bitmap_bh); | |
3032 | if (err) | |
3033 | goto out_err; | |
3034 | ||
3035 | err = -EIO; | |
3036 | gdp = ext4_get_group_desc(sb, ac->ac_b_ex.fe_group, &gdp_bh); | |
3037 | if (!gdp) | |
3038 | goto out_err; | |
3039 | ||
3040 | err = ext4_journal_get_write_access(handle, gdp_bh); | |
3041 | if (err) | |
3042 | goto out_err; | |
3043 | ||
3044 | block = ac->ac_b_ex.fe_group * EXT4_BLOCKS_PER_GROUP(sb) | |
3045 | + ac->ac_b_ex.fe_start | |
3046 | + le32_to_cpu(es->s_first_data_block); | |
3047 | ||
3048 | if (block == ext4_block_bitmap(sb, gdp) || | |
3049 | block == ext4_inode_bitmap(sb, gdp) || | |
3050 | in_range(block, ext4_inode_table(sb, gdp), | |
3051 | EXT4_SB(sb)->s_itb_per_group)) { | |
3052 | ||
3053 | ext4_error(sb, __FUNCTION__, | |
3054 | "Allocating block in system zone - block = %llu", | |
3055 | block); | |
3056 | } | |
3057 | #ifdef AGGRESSIVE_CHECK | |
3058 | { | |
3059 | int i; | |
3060 | for (i = 0; i < ac->ac_b_ex.fe_len; i++) { | |
3061 | BUG_ON(mb_test_bit(ac->ac_b_ex.fe_start + i, | |
3062 | bitmap_bh->b_data)); | |
3063 | } | |
3064 | } | |
3065 | #endif | |
3066 | mb_set_bits(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group), bitmap_bh->b_data, | |
3067 | ac->ac_b_ex.fe_start, ac->ac_b_ex.fe_len); | |
3068 | ||
3069 | spin_lock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group)); | |
3070 | if (gdp->bg_flags & cpu_to_le16(EXT4_BG_BLOCK_UNINIT)) { | |
3071 | gdp->bg_flags &= cpu_to_le16(~EXT4_BG_BLOCK_UNINIT); | |
3072 | gdp->bg_free_blocks_count = | |
3073 | cpu_to_le16(ext4_free_blocks_after_init(sb, | |
3074 | ac->ac_b_ex.fe_group, | |
3075 | gdp)); | |
3076 | } | |
3077 | gdp->bg_free_blocks_count = | |
3078 | cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count) | |
3079 | - ac->ac_b_ex.fe_len); | |
3080 | gdp->bg_checksum = ext4_group_desc_csum(sbi, ac->ac_b_ex.fe_group, gdp); | |
3081 | spin_unlock(sb_bgl_lock(sbi, ac->ac_b_ex.fe_group)); | |
3082 | percpu_counter_sub(&sbi->s_freeblocks_counter, ac->ac_b_ex.fe_len); | |
3083 | ||
3084 | err = ext4_journal_dirty_metadata(handle, bitmap_bh); | |
3085 | if (err) | |
3086 | goto out_err; | |
3087 | err = ext4_journal_dirty_metadata(handle, gdp_bh); | |
3088 | ||
3089 | out_err: | |
3090 | sb->s_dirt = 1; | |
42a10add | 3091 | brelse(bitmap_bh); |
c9de560d AT |
3092 | return err; |
3093 | } | |
3094 | ||
3095 | /* | |
3096 | * here we normalize request for locality group | |
3097 | * Group request are normalized to s_strip size if we set the same via mount | |
3098 | * option. If not we set it to s_mb_group_prealloc which can be configured via | |
3099 | * /proc/fs/ext4/<partition>/group_prealloc | |
3100 | * | |
3101 | * XXX: should we try to preallocate more than the group has now? | |
3102 | */ | |
3103 | static void ext4_mb_normalize_group_request(struct ext4_allocation_context *ac) | |
3104 | { | |
3105 | struct super_block *sb = ac->ac_sb; | |
3106 | struct ext4_locality_group *lg = ac->ac_lg; | |
3107 | ||
3108 | BUG_ON(lg == NULL); | |
3109 | if (EXT4_SB(sb)->s_stripe) | |
3110 | ac->ac_g_ex.fe_len = EXT4_SB(sb)->s_stripe; | |
3111 | else | |
3112 | ac->ac_g_ex.fe_len = EXT4_SB(sb)->s_mb_group_prealloc; | |
3113 | mb_debug("#%u: goal %lu blocks for locality group\n", | |
3114 | current->pid, ac->ac_g_ex.fe_len); | |
3115 | } | |
3116 | ||
3117 | /* | |
3118 | * Normalization means making request better in terms of | |
3119 | * size and alignment | |
3120 | */ | |
3121 | static void ext4_mb_normalize_request(struct ext4_allocation_context *ac, | |
3122 | struct ext4_allocation_request *ar) | |
3123 | { | |
3124 | int bsbits, max; | |
3125 | ext4_lblk_t end; | |
3126 | struct list_head *cur; | |
3127 | loff_t size, orig_size, start_off; | |
3128 | ext4_lblk_t start, orig_start; | |
3129 | struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); | |
3130 | ||
3131 | /* do normalize only data requests, metadata requests | |
3132 | do not need preallocation */ | |
3133 | if (!(ac->ac_flags & EXT4_MB_HINT_DATA)) | |
3134 | return; | |
3135 | ||
3136 | /* sometime caller may want exact blocks */ | |
3137 | if (unlikely(ac->ac_flags & EXT4_MB_HINT_GOAL_ONLY)) | |
3138 | return; | |
3139 | ||
3140 | /* caller may indicate that preallocation isn't | |
3141 | * required (it's a tail, for example) */ | |
3142 | if (ac->ac_flags & EXT4_MB_HINT_NOPREALLOC) | |
3143 | return; | |
3144 | ||
3145 | if (ac->ac_flags & EXT4_MB_HINT_GROUP_ALLOC) { | |
3146 | ext4_mb_normalize_group_request(ac); | |
3147 | return ; | |
3148 | } | |
3149 | ||
3150 | bsbits = ac->ac_sb->s_blocksize_bits; | |
3151 | ||
3152 | /* first, let's learn actual file size | |
3153 | * given current request is allocated */ | |
3154 | size = ac->ac_o_ex.fe_logical + ac->ac_o_ex.fe_len; | |
3155 | size = size << bsbits; | |
3156 | if (size < i_size_read(ac->ac_inode)) | |
3157 | size = i_size_read(ac->ac_inode); | |
3158 | ||
3159 | /* max available blocks in a free group */ | |
3160 | max = EXT4_BLOCKS_PER_GROUP(ac->ac_sb) - 1 - 1 - | |
3161 | EXT4_SB(ac->ac_sb)->s_itb_per_group; | |
3162 | ||
3163 | #define NRL_CHECK_SIZE(req, size, max,bits) \ | |
3164 | (req <= (size) || max <= ((size) >> bits)) | |
3165 | ||
3166 | /* first, try to predict filesize */ | |
3167 | /* XXX: should this table be tunable? */ | |
3168 | start_off = 0; | |
3169 | if (size <= 16 * 1024) { | |
3170 | size = 16 * 1024; | |
3171 | } else if (size <= 32 * 1024) { | |
3172 | size = 32 * 1024; | |
3173 | } else if (size <= 64 * 1024) { | |
3174 | size = 64 * 1024; | |
3175 | } else if (size <= 128 * 1024) { | |
3176 | size = 128 * 1024; | |
3177 | } else if (size <= 256 * 1024) { | |
3178 | size = 256 * 1024; | |
3179 | } else if (size <= 512 * 1024) { | |
3180 | size = 512 * 1024; | |
3181 | } else if (size <= 1024 * 1024) { | |
3182 | size = 1024 * 1024; | |
3183 | } else if (NRL_CHECK_SIZE(size, 4 * 1024 * 1024, max, bsbits)) { | |
3184 | start_off = ((loff_t)ac->ac_o_ex.fe_logical >> | |
3185 | (20 - bsbits)) << 20; | |
3186 | size = 1024 * 1024; | |
3187 | } else if (NRL_CHECK_SIZE(size, 8 * 1024 * 1024, max, bsbits)) { | |
3188 | start_off = ((loff_t)ac->ac_o_ex.fe_logical >> | |
3189 | (22 - bsbits)) << 22; | |
3190 | size = 4 * 1024 * 1024; | |
3191 | } else if (NRL_CHECK_SIZE(ac->ac_o_ex.fe_len, | |
3192 | (8<<20)>>bsbits, max, bsbits)) { | |
3193 | start_off = ((loff_t)ac->ac_o_ex.fe_logical >> | |
3194 | (23 - bsbits)) << 23; | |
3195 | size = 8 * 1024 * 1024; | |
3196 | } else { | |
3197 | start_off = (loff_t)ac->ac_o_ex.fe_logical << bsbits; | |
3198 | size = ac->ac_o_ex.fe_len << bsbits; | |
3199 | } | |
3200 | orig_size = size = size >> bsbits; | |
3201 | orig_start = start = start_off >> bsbits; | |
3202 | ||
3203 | /* don't cover already allocated blocks in selected range */ | |
3204 | if (ar->pleft && start <= ar->lleft) { | |
3205 | size -= ar->lleft + 1 - start; | |
3206 | start = ar->lleft + 1; | |
3207 | } | |
3208 | if (ar->pright && start + size - 1 >= ar->lright) | |
3209 | size -= start + size - ar->lright; | |
3210 | ||
3211 | end = start + size; | |
3212 | ||
3213 | /* check we don't cross already preallocated blocks */ | |
3214 | rcu_read_lock(); | |
3215 | list_for_each_rcu(cur, &ei->i_prealloc_list) { | |
3216 | struct ext4_prealloc_space *pa; | |
3217 | unsigned long pa_end; | |
3218 | ||
3219 | pa = list_entry(cur, struct ext4_prealloc_space, pa_inode_list); | |
3220 | ||
3221 | if (pa->pa_deleted) | |
3222 | continue; | |
3223 | spin_lock(&pa->pa_lock); | |
3224 | if (pa->pa_deleted) { | |
3225 | spin_unlock(&pa->pa_lock); | |
3226 | continue; | |
3227 | } | |
3228 | ||
3229 | pa_end = pa->pa_lstart + pa->pa_len; | |
3230 | ||
3231 | /* PA must not overlap original request */ | |
3232 | BUG_ON(!(ac->ac_o_ex.fe_logical >= pa_end || | |
3233 | ac->ac_o_ex.fe_logical < pa->pa_lstart)); | |
3234 | ||
3235 | /* skip PA normalized request doesn't overlap with */ | |
3236 | if (pa->pa_lstart >= end) { | |
3237 | spin_unlock(&pa->pa_lock); | |
3238 | continue; | |
3239 | } | |
3240 | if (pa_end <= start) { | |
3241 | spin_unlock(&pa->pa_lock); | |
3242 | continue; | |
3243 | } | |
3244 | BUG_ON(pa->pa_lstart <= start && pa_end >= end); | |
3245 | ||
3246 | if (pa_end <= ac->ac_o_ex.fe_logical) { | |
3247 | BUG_ON(pa_end < start); | |
3248 | start = pa_end; | |
3249 | } | |
3250 | ||
3251 | if (pa->pa_lstart > ac->ac_o_ex.fe_logical) { | |
3252 | BUG_ON(pa->pa_lstart > end); | |
3253 | end = pa->pa_lstart; | |
3254 | } | |
3255 | spin_unlock(&pa->pa_lock); | |
3256 | } | |
3257 | rcu_read_unlock(); | |
3258 | size = end - start; | |
3259 | ||
3260 | /* XXX: extra loop to check we really don't overlap preallocations */ | |
3261 | rcu_read_lock(); | |
3262 | list_for_each_rcu(cur, &ei->i_prealloc_list) { | |
3263 | struct ext4_prealloc_space *pa; | |
3264 | unsigned long pa_end; | |
3265 | pa = list_entry(cur, struct ext4_prealloc_space, pa_inode_list); | |
3266 | spin_lock(&pa->pa_lock); | |
3267 | if (pa->pa_deleted == 0) { | |
3268 | pa_end = pa->pa_lstart + pa->pa_len; | |
3269 | BUG_ON(!(start >= pa_end || end <= pa->pa_lstart)); | |
3270 | } | |
3271 | spin_unlock(&pa->pa_lock); | |
3272 | } | |
3273 | rcu_read_unlock(); | |
3274 | ||
3275 | if (start + size <= ac->ac_o_ex.fe_logical && | |
3276 | start > ac->ac_o_ex.fe_logical) { | |
3277 | printk(KERN_ERR "start %lu, size %lu, fe_logical %lu\n", | |
3278 | (unsigned long) start, (unsigned long) size, | |
3279 | (unsigned long) ac->ac_o_ex.fe_logical); | |
3280 | } | |
3281 | BUG_ON(start + size <= ac->ac_o_ex.fe_logical && | |
3282 | start > ac->ac_o_ex.fe_logical); | |
3283 | BUG_ON(size <= 0 || size >= EXT4_BLOCKS_PER_GROUP(ac->ac_sb)); | |
3284 | ||
3285 | /* now prepare goal request */ | |
3286 | ||
3287 | /* XXX: is it better to align blocks WRT to logical | |
3288 | * placement or satisfy big request as is */ | |
3289 | ac->ac_g_ex.fe_logical = start; | |
3290 | ac->ac_g_ex.fe_len = size; | |
3291 | ||
3292 | /* define goal start in order to merge */ | |
3293 | if (ar->pright && (ar->lright == (start + size))) { | |
3294 | /* merge to the right */ | |
3295 | ext4_get_group_no_and_offset(ac->ac_sb, ar->pright - size, | |
3296 | &ac->ac_f_ex.fe_group, | |
3297 | &ac->ac_f_ex.fe_start); | |
3298 | ac->ac_flags |= EXT4_MB_HINT_TRY_GOAL; | |
3299 | } | |
3300 | if (ar->pleft && (ar->lleft + 1 == start)) { | |
3301 | /* merge to the left */ | |
3302 | ext4_get_group_no_and_offset(ac->ac_sb, ar->pleft + 1, | |
3303 | &ac->ac_f_ex.fe_group, | |
3304 | &ac->ac_f_ex.fe_start); | |
3305 | ac->ac_flags |= EXT4_MB_HINT_TRY_GOAL; | |
3306 | } | |
3307 | ||
3308 | mb_debug("goal: %u(was %u) blocks at %u\n", (unsigned) size, | |
3309 | (unsigned) orig_size, (unsigned) start); | |
3310 | } | |
3311 | ||
3312 | static void ext4_mb_collect_stats(struct ext4_allocation_context *ac) | |
3313 | { | |
3314 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
3315 | ||
3316 | if (sbi->s_mb_stats && ac->ac_g_ex.fe_len > 1) { | |
3317 | atomic_inc(&sbi->s_bal_reqs); | |
3318 | atomic_add(ac->ac_b_ex.fe_len, &sbi->s_bal_allocated); | |
3319 | if (ac->ac_o_ex.fe_len >= ac->ac_g_ex.fe_len) | |
3320 | atomic_inc(&sbi->s_bal_success); | |
3321 | atomic_add(ac->ac_found, &sbi->s_bal_ex_scanned); | |
3322 | if (ac->ac_g_ex.fe_start == ac->ac_b_ex.fe_start && | |
3323 | ac->ac_g_ex.fe_group == ac->ac_b_ex.fe_group) | |
3324 | atomic_inc(&sbi->s_bal_goals); | |
3325 | if (ac->ac_found > sbi->s_mb_max_to_scan) | |
3326 | atomic_inc(&sbi->s_bal_breaks); | |
3327 | } | |
3328 | ||
3329 | ext4_mb_store_history(ac); | |
3330 | } | |
3331 | ||
3332 | /* | |
3333 | * use blocks preallocated to inode | |
3334 | */ | |
3335 | static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac, | |
3336 | struct ext4_prealloc_space *pa) | |
3337 | { | |
3338 | ext4_fsblk_t start; | |
3339 | ext4_fsblk_t end; | |
3340 | int len; | |
3341 | ||
3342 | /* found preallocated blocks, use them */ | |
3343 | start = pa->pa_pstart + (ac->ac_o_ex.fe_logical - pa->pa_lstart); | |
3344 | end = min(pa->pa_pstart + pa->pa_len, start + ac->ac_o_ex.fe_len); | |
3345 | len = end - start; | |
3346 | ext4_get_group_no_and_offset(ac->ac_sb, start, &ac->ac_b_ex.fe_group, | |
3347 | &ac->ac_b_ex.fe_start); | |
3348 | ac->ac_b_ex.fe_len = len; | |
3349 | ac->ac_status = AC_STATUS_FOUND; | |
3350 | ac->ac_pa = pa; | |
3351 | ||
3352 | BUG_ON(start < pa->pa_pstart); | |
3353 | BUG_ON(start + len > pa->pa_pstart + pa->pa_len); | |
3354 | BUG_ON(pa->pa_free < len); | |
3355 | pa->pa_free -= len; | |
3356 | ||
3357 | mb_debug("use %llu/%lu from inode pa %p\n", start, len, pa); | |
3358 | } | |
3359 | ||
3360 | /* | |
3361 | * use blocks preallocated to locality group | |
3362 | */ | |
3363 | static void ext4_mb_use_group_pa(struct ext4_allocation_context *ac, | |
3364 | struct ext4_prealloc_space *pa) | |
3365 | { | |
3366 | unsigned len = ac->ac_o_ex.fe_len; | |
3367 | ||
3368 | ext4_get_group_no_and_offset(ac->ac_sb, pa->pa_pstart, | |
3369 | &ac->ac_b_ex.fe_group, | |
3370 | &ac->ac_b_ex.fe_start); | |
3371 | ac->ac_b_ex.fe_len = len; | |
3372 | ac->ac_status = AC_STATUS_FOUND; | |
3373 | ac->ac_pa = pa; | |
3374 | ||
3375 | /* we don't correct pa_pstart or pa_plen here to avoid | |
26346ff6 | 3376 | * possible race when the group is being loaded concurrently |
c9de560d | 3377 | * instead we correct pa later, after blocks are marked |
26346ff6 AK |
3378 | * in on-disk bitmap -- see ext4_mb_release_context() |
3379 | * Other CPUs are prevented from allocating from this pa by lg_mutex | |
c9de560d AT |
3380 | */ |
3381 | mb_debug("use %u/%u from group pa %p\n", pa->pa_lstart-len, len, pa); | |
3382 | } | |
3383 | ||
3384 | /* | |
3385 | * search goal blocks in preallocated space | |
3386 | */ | |
3387 | static int ext4_mb_use_preallocated(struct ext4_allocation_context *ac) | |
3388 | { | |
3389 | struct ext4_inode_info *ei = EXT4_I(ac->ac_inode); | |
3390 | struct ext4_locality_group *lg; | |
3391 | struct ext4_prealloc_space *pa; | |
3392 | struct list_head *cur; | |
3393 | ||
3394 | /* only data can be preallocated */ | |
3395 | if (!(ac->ac_flags & EXT4_MB_HINT_DATA)) | |
3396 | return 0; | |
3397 | ||
3398 | /* first, try per-file preallocation */ | |
3399 | rcu_read_lock(); | |
3400 | list_for_each_rcu(cur, &ei->i_prealloc_list) { | |
3401 | pa = list_entry(cur, struct ext4_prealloc_space, pa_inode_list); | |
3402 | ||
3403 | /* all fields in this condition don't change, | |
3404 | * so we can skip locking for them */ | |
3405 | if (ac->ac_o_ex.fe_logical < pa->pa_lstart || | |
3406 | ac->ac_o_ex.fe_logical >= pa->pa_lstart + pa->pa_len) | |
3407 | continue; | |
3408 | ||
3409 | /* found preallocated blocks, use them */ | |
3410 | spin_lock(&pa->pa_lock); | |
3411 | if (pa->pa_deleted == 0 && pa->pa_free) { | |
3412 | atomic_inc(&pa->pa_count); | |
3413 | ext4_mb_use_inode_pa(ac, pa); | |
3414 | spin_unlock(&pa->pa_lock); | |
3415 | ac->ac_criteria = 10; | |
3416 | rcu_read_unlock(); | |
3417 | return 1; | |
3418 | } | |
3419 | spin_unlock(&pa->pa_lock); | |
3420 | } | |
3421 | rcu_read_unlock(); | |
3422 | ||
3423 | /* can we use group allocation? */ | |
3424 | if (!(ac->ac_flags & EXT4_MB_HINT_GROUP_ALLOC)) | |
3425 | return 0; | |
3426 | ||
3427 | /* inode may have no locality group for some reason */ | |
3428 | lg = ac->ac_lg; | |
3429 | if (lg == NULL) | |
3430 | return 0; | |
3431 | ||
3432 | rcu_read_lock(); | |
3433 | list_for_each_rcu(cur, &lg->lg_prealloc_list) { | |
3434 | pa = list_entry(cur, struct ext4_prealloc_space, pa_inode_list); | |
3435 | spin_lock(&pa->pa_lock); | |
3436 | if (pa->pa_deleted == 0 && pa->pa_free >= ac->ac_o_ex.fe_len) { | |
3437 | atomic_inc(&pa->pa_count); | |
3438 | ext4_mb_use_group_pa(ac, pa); | |
3439 | spin_unlock(&pa->pa_lock); | |
3440 | ac->ac_criteria = 20; | |
3441 | rcu_read_unlock(); | |
3442 | return 1; | |
3443 | } | |
3444 | spin_unlock(&pa->pa_lock); | |
3445 | } | |
3446 | rcu_read_unlock(); | |
3447 | ||
3448 | return 0; | |
3449 | } | |
3450 | ||
3451 | /* | |
3452 | * the function goes through all preallocation in this group and marks them | |
3453 | * used in in-core bitmap. buddy must be generated from this bitmap | |
3454 | * Need to be called with ext4 group lock (ext4_lock_group) | |
3455 | */ | |
3456 | static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap, | |
3457 | ext4_group_t group) | |
3458 | { | |
3459 | struct ext4_group_info *grp = ext4_get_group_info(sb, group); | |
3460 | struct ext4_prealloc_space *pa; | |
3461 | struct list_head *cur; | |
3462 | ext4_group_t groupnr; | |
3463 | ext4_grpblk_t start; | |
3464 | int preallocated = 0; | |
3465 | int count = 0; | |
3466 | int len; | |
3467 | ||
3468 | /* all form of preallocation discards first load group, | |
3469 | * so the only competing code is preallocation use. | |
3470 | * we don't need any locking here | |
3471 | * notice we do NOT ignore preallocations with pa_deleted | |
3472 | * otherwise we could leave used blocks available for | |
3473 | * allocation in buddy when concurrent ext4_mb_put_pa() | |
3474 | * is dropping preallocation | |
3475 | */ | |
3476 | list_for_each(cur, &grp->bb_prealloc_list) { | |
3477 | pa = list_entry(cur, struct ext4_prealloc_space, pa_group_list); | |
3478 | spin_lock(&pa->pa_lock); | |
3479 | ext4_get_group_no_and_offset(sb, pa->pa_pstart, | |
3480 | &groupnr, &start); | |
3481 | len = pa->pa_len; | |
3482 | spin_unlock(&pa->pa_lock); | |
3483 | if (unlikely(len == 0)) | |
3484 | continue; | |
3485 | BUG_ON(groupnr != group); | |
3486 | mb_set_bits(sb_bgl_lock(EXT4_SB(sb), group), | |
3487 | bitmap, start, len); | |
3488 | preallocated += len; | |
3489 | count++; | |
3490 | } | |
3491 | mb_debug("prellocated %u for group %lu\n", preallocated, group); | |
3492 | } | |
3493 | ||
3494 | static void ext4_mb_pa_callback(struct rcu_head *head) | |
3495 | { | |
3496 | struct ext4_prealloc_space *pa; | |
3497 | pa = container_of(head, struct ext4_prealloc_space, u.pa_rcu); | |
3498 | kmem_cache_free(ext4_pspace_cachep, pa); | |
3499 | } | |
3500 | ||
3501 | /* | |
3502 | * drops a reference to preallocated space descriptor | |
3503 | * if this was the last reference and the space is consumed | |
3504 | */ | |
3505 | static void ext4_mb_put_pa(struct ext4_allocation_context *ac, | |
3506 | struct super_block *sb, struct ext4_prealloc_space *pa) | |
3507 | { | |
3508 | unsigned long grp; | |
3509 | ||
3510 | if (!atomic_dec_and_test(&pa->pa_count) || pa->pa_free != 0) | |
3511 | return; | |
3512 | ||
3513 | /* in this short window concurrent discard can set pa_deleted */ | |
3514 | spin_lock(&pa->pa_lock); | |
3515 | if (pa->pa_deleted == 1) { | |
3516 | spin_unlock(&pa->pa_lock); | |
3517 | return; | |
3518 | } | |
3519 | ||
3520 | pa->pa_deleted = 1; | |
3521 | spin_unlock(&pa->pa_lock); | |
3522 | ||
3523 | /* -1 is to protect from crossing allocation group */ | |
3524 | ext4_get_group_no_and_offset(sb, pa->pa_pstart - 1, &grp, NULL); | |
3525 | ||
3526 | /* | |
3527 | * possible race: | |
3528 | * | |
3529 | * P1 (buddy init) P2 (regular allocation) | |
3530 | * find block B in PA | |
3531 | * copy on-disk bitmap to buddy | |
3532 | * mark B in on-disk bitmap | |
3533 | * drop PA from group | |
3534 | * mark all PAs in buddy | |
3535 | * | |
3536 | * thus, P1 initializes buddy with B available. to prevent this | |
3537 | * we make "copy" and "mark all PAs" atomic and serialize "drop PA" | |
3538 | * against that pair | |
3539 | */ | |
3540 | ext4_lock_group(sb, grp); | |
3541 | list_del(&pa->pa_group_list); | |
3542 | ext4_unlock_group(sb, grp); | |
3543 | ||
3544 | spin_lock(pa->pa_obj_lock); | |
3545 | list_del_rcu(&pa->pa_inode_list); | |
3546 | spin_unlock(pa->pa_obj_lock); | |
3547 | ||
3548 | call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); | |
3549 | } | |
3550 | ||
3551 | /* | |
3552 | * creates new preallocated space for given inode | |
3553 | */ | |
3554 | static int ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) | |
3555 | { | |
3556 | struct super_block *sb = ac->ac_sb; | |
3557 | struct ext4_prealloc_space *pa; | |
3558 | struct ext4_group_info *grp; | |
3559 | struct ext4_inode_info *ei; | |
3560 | ||
3561 | /* preallocate only when found space is larger then requested */ | |
3562 | BUG_ON(ac->ac_o_ex.fe_len >= ac->ac_b_ex.fe_len); | |
3563 | BUG_ON(ac->ac_status != AC_STATUS_FOUND); | |
3564 | BUG_ON(!S_ISREG(ac->ac_inode->i_mode)); | |
3565 | ||
3566 | pa = kmem_cache_alloc(ext4_pspace_cachep, GFP_NOFS); | |
3567 | if (pa == NULL) | |
3568 | return -ENOMEM; | |
3569 | ||
3570 | if (ac->ac_b_ex.fe_len < ac->ac_g_ex.fe_len) { | |
3571 | int winl; | |
3572 | int wins; | |
3573 | int win; | |
3574 | int offs; | |
3575 | ||
3576 | /* we can't allocate as much as normalizer wants. | |
3577 | * so, found space must get proper lstart | |
3578 | * to cover original request */ | |
3579 | BUG_ON(ac->ac_g_ex.fe_logical > ac->ac_o_ex.fe_logical); | |
3580 | BUG_ON(ac->ac_g_ex.fe_len < ac->ac_o_ex.fe_len); | |
3581 | ||
3582 | /* we're limited by original request in that | |
3583 | * logical block must be covered any way | |
3584 | * winl is window we can move our chunk within */ | |
3585 | winl = ac->ac_o_ex.fe_logical - ac->ac_g_ex.fe_logical; | |
3586 | ||
3587 | /* also, we should cover whole original request */ | |
3588 | wins = ac->ac_b_ex.fe_len - ac->ac_o_ex.fe_len; | |
3589 | ||
3590 | /* the smallest one defines real window */ | |
3591 | win = min(winl, wins); | |
3592 | ||
3593 | offs = ac->ac_o_ex.fe_logical % ac->ac_b_ex.fe_len; | |
3594 | if (offs && offs < win) | |
3595 | win = offs; | |
3596 | ||
3597 | ac->ac_b_ex.fe_logical = ac->ac_o_ex.fe_logical - win; | |
3598 | BUG_ON(ac->ac_o_ex.fe_logical < ac->ac_b_ex.fe_logical); | |
3599 | BUG_ON(ac->ac_o_ex.fe_len > ac->ac_b_ex.fe_len); | |
3600 | } | |
3601 | ||
3602 | /* preallocation can change ac_b_ex, thus we store actually | |
3603 | * allocated blocks for history */ | |
3604 | ac->ac_f_ex = ac->ac_b_ex; | |
3605 | ||
3606 | pa->pa_lstart = ac->ac_b_ex.fe_logical; | |
3607 | pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex); | |
3608 | pa->pa_len = ac->ac_b_ex.fe_len; | |
3609 | pa->pa_free = pa->pa_len; | |
3610 | atomic_set(&pa->pa_count, 1); | |
3611 | spin_lock_init(&pa->pa_lock); | |
3612 | pa->pa_deleted = 0; | |
3613 | pa->pa_linear = 0; | |
3614 | ||
3615 | mb_debug("new inode pa %p: %llu/%u for %u\n", pa, | |
3616 | pa->pa_pstart, pa->pa_len, pa->pa_lstart); | |
3617 | ||
3618 | ext4_mb_use_inode_pa(ac, pa); | |
3619 | atomic_add(pa->pa_free, &EXT4_SB(sb)->s_mb_preallocated); | |
3620 | ||
3621 | ei = EXT4_I(ac->ac_inode); | |
3622 | grp = ext4_get_group_info(sb, ac->ac_b_ex.fe_group); | |
3623 | ||
3624 | pa->pa_obj_lock = &ei->i_prealloc_lock; | |
3625 | pa->pa_inode = ac->ac_inode; | |
3626 | ||
3627 | ext4_lock_group(sb, ac->ac_b_ex.fe_group); | |
3628 | list_add(&pa->pa_group_list, &grp->bb_prealloc_list); | |
3629 | ext4_unlock_group(sb, ac->ac_b_ex.fe_group); | |
3630 | ||
3631 | spin_lock(pa->pa_obj_lock); | |
3632 | list_add_rcu(&pa->pa_inode_list, &ei->i_prealloc_list); | |
3633 | spin_unlock(pa->pa_obj_lock); | |
3634 | ||
3635 | return 0; | |
3636 | } | |
3637 | ||
3638 | /* | |
3639 | * creates new preallocated space for locality group inodes belongs to | |
3640 | */ | |
3641 | static int ext4_mb_new_group_pa(struct ext4_allocation_context *ac) | |
3642 | { | |
3643 | struct super_block *sb = ac->ac_sb; | |
3644 | struct ext4_locality_group *lg; | |
3645 | struct ext4_prealloc_space *pa; | |
3646 | struct ext4_group_info *grp; | |
3647 | ||
3648 | /* preallocate only when found space is larger then requested */ | |
3649 | BUG_ON(ac->ac_o_ex.fe_len >= ac->ac_b_ex.fe_len); | |
3650 | BUG_ON(ac->ac_status != AC_STATUS_FOUND); | |
3651 | BUG_ON(!S_ISREG(ac->ac_inode->i_mode)); | |
3652 | ||
3653 | BUG_ON(ext4_pspace_cachep == NULL); | |
3654 | pa = kmem_cache_alloc(ext4_pspace_cachep, GFP_NOFS); | |
3655 | if (pa == NULL) | |
3656 | return -ENOMEM; | |
3657 | ||
3658 | /* preallocation can change ac_b_ex, thus we store actually | |
3659 | * allocated blocks for history */ | |
3660 | ac->ac_f_ex = ac->ac_b_ex; | |
3661 | ||
3662 | pa->pa_pstart = ext4_grp_offs_to_block(sb, &ac->ac_b_ex); | |
3663 | pa->pa_lstart = pa->pa_pstart; | |
3664 | pa->pa_len = ac->ac_b_ex.fe_len; | |
3665 | pa->pa_free = pa->pa_len; | |
3666 | atomic_set(&pa->pa_count, 1); | |
3667 | spin_lock_init(&pa->pa_lock); | |
3668 | pa->pa_deleted = 0; | |
3669 | pa->pa_linear = 1; | |
3670 | ||
3671 | mb_debug("new group pa %p: %llu/%u for %u\n", pa, | |
3672 | pa->pa_pstart, pa->pa_len, pa->pa_lstart); | |
3673 | ||
3674 | ext4_mb_use_group_pa(ac, pa); | |
3675 | atomic_add(pa->pa_free, &EXT4_SB(sb)->s_mb_preallocated); | |
3676 | ||
3677 | grp = ext4_get_group_info(sb, ac->ac_b_ex.fe_group); | |
3678 | lg = ac->ac_lg; | |
3679 | BUG_ON(lg == NULL); | |
3680 | ||
3681 | pa->pa_obj_lock = &lg->lg_prealloc_lock; | |
3682 | pa->pa_inode = NULL; | |
3683 | ||
3684 | ext4_lock_group(sb, ac->ac_b_ex.fe_group); | |
3685 | list_add(&pa->pa_group_list, &grp->bb_prealloc_list); | |
3686 | ext4_unlock_group(sb, ac->ac_b_ex.fe_group); | |
3687 | ||
3688 | spin_lock(pa->pa_obj_lock); | |
3689 | list_add_tail_rcu(&pa->pa_inode_list, &lg->lg_prealloc_list); | |
3690 | spin_unlock(pa->pa_obj_lock); | |
3691 | ||
3692 | return 0; | |
3693 | } | |
3694 | ||
3695 | static int ext4_mb_new_preallocation(struct ext4_allocation_context *ac) | |
3696 | { | |
3697 | int err; | |
3698 | ||
3699 | if (ac->ac_flags & EXT4_MB_HINT_GROUP_ALLOC) | |
3700 | err = ext4_mb_new_group_pa(ac); | |
3701 | else | |
3702 | err = ext4_mb_new_inode_pa(ac); | |
3703 | return err; | |
3704 | } | |
3705 | ||
3706 | /* | |
3707 | * finds all unused blocks in on-disk bitmap, frees them in | |
3708 | * in-core bitmap and buddy. | |
3709 | * @pa must be unlinked from inode and group lists, so that | |
3710 | * nobody else can find/use it. | |
3711 | * the caller MUST hold group/inode locks. | |
3712 | * TODO: optimize the case when there are no in-core structures yet | |
3713 | */ | |
3714 | static int ext4_mb_release_inode_pa(struct ext4_buddy *e4b, | |
3715 | struct buffer_head *bitmap_bh, | |
3716 | struct ext4_prealloc_space *pa) | |
3717 | { | |
256bdb49 | 3718 | struct ext4_allocation_context *ac; |
c9de560d AT |
3719 | struct super_block *sb = e4b->bd_sb; |
3720 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
3721 | unsigned long end; | |
3722 | unsigned long next; | |
3723 | ext4_group_t group; | |
3724 | ext4_grpblk_t bit; | |
3725 | sector_t start; | |
3726 | int err = 0; | |
3727 | int free = 0; | |
3728 | ||
3729 | BUG_ON(pa->pa_deleted == 0); | |
3730 | ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit); | |
3731 | BUG_ON(group != e4b->bd_group && pa->pa_len != 0); | |
3732 | end = bit + pa->pa_len; | |
3733 | ||
256bdb49 ES |
3734 | ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS); |
3735 | ||
3736 | if (ac) { | |
3737 | ac->ac_sb = sb; | |
3738 | ac->ac_inode = pa->pa_inode; | |
3739 | ac->ac_op = EXT4_MB_HISTORY_DISCARD; | |
3740 | } | |
c9de560d AT |
3741 | |
3742 | while (bit < end) { | |
3743 | bit = ext4_find_next_zero_bit(bitmap_bh->b_data, end, bit); | |
3744 | if (bit >= end) | |
3745 | break; | |
3746 | next = ext4_find_next_bit(bitmap_bh->b_data, end, bit); | |
3747 | if (next > end) | |
3748 | next = end; | |
3749 | start = group * EXT4_BLOCKS_PER_GROUP(sb) + bit + | |
3750 | le32_to_cpu(sbi->s_es->s_first_data_block); | |
3751 | mb_debug(" free preallocated %u/%u in group %u\n", | |
3752 | (unsigned) start, (unsigned) next - bit, | |
3753 | (unsigned) group); | |
3754 | free += next - bit; | |
3755 | ||
256bdb49 ES |
3756 | if (ac) { |
3757 | ac->ac_b_ex.fe_group = group; | |
3758 | ac->ac_b_ex.fe_start = bit; | |
3759 | ac->ac_b_ex.fe_len = next - bit; | |
3760 | ac->ac_b_ex.fe_logical = 0; | |
3761 | ext4_mb_store_history(ac); | |
3762 | } | |
c9de560d AT |
3763 | |
3764 | mb_free_blocks(pa->pa_inode, e4b, bit, next - bit); | |
3765 | bit = next + 1; | |
3766 | } | |
3767 | if (free != pa->pa_free) { | |
26346ff6 | 3768 | printk(KERN_CRIT "pa %p: logic %lu, phys. %lu, len %lu\n", |
c9de560d AT |
3769 | pa, (unsigned long) pa->pa_lstart, |
3770 | (unsigned long) pa->pa_pstart, | |
3771 | (unsigned long) pa->pa_len); | |
26346ff6 AK |
3772 | ext4_error(sb, __FUNCTION__, "free %u, pa_free %u\n", |
3773 | free, pa->pa_free); | |
c9de560d | 3774 | } |
c9de560d | 3775 | atomic_add(free, &sbi->s_mb_discarded); |
256bdb49 ES |
3776 | if (ac) |
3777 | kmem_cache_free(ext4_ac_cachep, ac); | |
c9de560d AT |
3778 | |
3779 | return err; | |
3780 | } | |
3781 | ||
3782 | static int ext4_mb_release_group_pa(struct ext4_buddy *e4b, | |
3783 | struct ext4_prealloc_space *pa) | |
3784 | { | |
256bdb49 | 3785 | struct ext4_allocation_context *ac; |
c9de560d AT |
3786 | struct super_block *sb = e4b->bd_sb; |
3787 | ext4_group_t group; | |
3788 | ext4_grpblk_t bit; | |
3789 | ||
256bdb49 ES |
3790 | ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS); |
3791 | ||
3792 | if (ac) | |
3793 | ac->ac_op = EXT4_MB_HISTORY_DISCARD; | |
c9de560d AT |
3794 | |
3795 | BUG_ON(pa->pa_deleted == 0); | |
3796 | ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, &bit); | |
3797 | BUG_ON(group != e4b->bd_group && pa->pa_len != 0); | |
3798 | mb_free_blocks(pa->pa_inode, e4b, bit, pa->pa_len); | |
3799 | atomic_add(pa->pa_len, &EXT4_SB(sb)->s_mb_discarded); | |
3800 | ||
256bdb49 ES |
3801 | if (ac) { |
3802 | ac->ac_sb = sb; | |
3803 | ac->ac_inode = NULL; | |
3804 | ac->ac_b_ex.fe_group = group; | |
3805 | ac->ac_b_ex.fe_start = bit; | |
3806 | ac->ac_b_ex.fe_len = pa->pa_len; | |
3807 | ac->ac_b_ex.fe_logical = 0; | |
3808 | ext4_mb_store_history(ac); | |
3809 | kmem_cache_free(ext4_ac_cachep, ac); | |
3810 | } | |
c9de560d AT |
3811 | |
3812 | return 0; | |
3813 | } | |
3814 | ||
3815 | /* | |
3816 | * releases all preallocations in given group | |
3817 | * | |
3818 | * first, we need to decide discard policy: | |
3819 | * - when do we discard | |
3820 | * 1) ENOSPC | |
3821 | * - how many do we discard | |
3822 | * 1) how many requested | |
3823 | */ | |
3824 | static int ext4_mb_discard_group_preallocations(struct super_block *sb, | |
3825 | ext4_group_t group, int needed) | |
3826 | { | |
3827 | struct ext4_group_info *grp = ext4_get_group_info(sb, group); | |
3828 | struct buffer_head *bitmap_bh = NULL; | |
3829 | struct ext4_prealloc_space *pa, *tmp; | |
3830 | struct list_head list; | |
3831 | struct ext4_buddy e4b; | |
3832 | int err; | |
3833 | int busy = 0; | |
3834 | int free = 0; | |
3835 | ||
3836 | mb_debug("discard preallocation for group %lu\n", group); | |
3837 | ||
3838 | if (list_empty(&grp->bb_prealloc_list)) | |
3839 | return 0; | |
3840 | ||
3841 | bitmap_bh = read_block_bitmap(sb, group); | |
3842 | if (bitmap_bh == NULL) { | |
3843 | /* error handling here */ | |
3844 | ext4_mb_release_desc(&e4b); | |
3845 | BUG_ON(bitmap_bh == NULL); | |
3846 | } | |
3847 | ||
3848 | err = ext4_mb_load_buddy(sb, group, &e4b); | |
3849 | BUG_ON(err != 0); /* error handling here */ | |
3850 | ||
3851 | if (needed == 0) | |
3852 | needed = EXT4_BLOCKS_PER_GROUP(sb) + 1; | |
3853 | ||
3854 | grp = ext4_get_group_info(sb, group); | |
3855 | INIT_LIST_HEAD(&list); | |
3856 | ||
3857 | repeat: | |
3858 | ext4_lock_group(sb, group); | |
3859 | list_for_each_entry_safe(pa, tmp, | |
3860 | &grp->bb_prealloc_list, pa_group_list) { | |
3861 | spin_lock(&pa->pa_lock); | |
3862 | if (atomic_read(&pa->pa_count)) { | |
3863 | spin_unlock(&pa->pa_lock); | |
3864 | busy = 1; | |
3865 | continue; | |
3866 | } | |
3867 | if (pa->pa_deleted) { | |
3868 | spin_unlock(&pa->pa_lock); | |
3869 | continue; | |
3870 | } | |
3871 | ||
3872 | /* seems this one can be freed ... */ | |
3873 | pa->pa_deleted = 1; | |
3874 | ||
3875 | /* we can trust pa_free ... */ | |
3876 | free += pa->pa_free; | |
3877 | ||
3878 | spin_unlock(&pa->pa_lock); | |
3879 | ||
3880 | list_del(&pa->pa_group_list); | |
3881 | list_add(&pa->u.pa_tmp_list, &list); | |
3882 | } | |
3883 | ||
3884 | /* if we still need more blocks and some PAs were used, try again */ | |
3885 | if (free < needed && busy) { | |
3886 | busy = 0; | |
3887 | ext4_unlock_group(sb, group); | |
3888 | /* | |
3889 | * Yield the CPU here so that we don't get soft lockup | |
3890 | * in non preempt case. | |
3891 | */ | |
3892 | yield(); | |
3893 | goto repeat; | |
3894 | } | |
3895 | ||
3896 | /* found anything to free? */ | |
3897 | if (list_empty(&list)) { | |
3898 | BUG_ON(free != 0); | |
3899 | goto out; | |
3900 | } | |
3901 | ||
3902 | /* now free all selected PAs */ | |
3903 | list_for_each_entry_safe(pa, tmp, &list, u.pa_tmp_list) { | |
3904 | ||
3905 | /* remove from object (inode or locality group) */ | |
3906 | spin_lock(pa->pa_obj_lock); | |
3907 | list_del_rcu(&pa->pa_inode_list); | |
3908 | spin_unlock(pa->pa_obj_lock); | |
3909 | ||
3910 | if (pa->pa_linear) | |
3911 | ext4_mb_release_group_pa(&e4b, pa); | |
3912 | else | |
3913 | ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa); | |
3914 | ||
3915 | list_del(&pa->u.pa_tmp_list); | |
3916 | call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); | |
3917 | } | |
3918 | ||
3919 | out: | |
3920 | ext4_unlock_group(sb, group); | |
3921 | ext4_mb_release_desc(&e4b); | |
3922 | put_bh(bitmap_bh); | |
3923 | return free; | |
3924 | } | |
3925 | ||
3926 | /* | |
3927 | * releases all non-used preallocated blocks for given inode | |
3928 | * | |
3929 | * It's important to discard preallocations under i_data_sem | |
3930 | * We don't want another block to be served from the prealloc | |
3931 | * space when we are discarding the inode prealloc space. | |
3932 | * | |
3933 | * FIXME!! Make sure it is valid at all the call sites | |
3934 | */ | |
3935 | void ext4_mb_discard_inode_preallocations(struct inode *inode) | |
3936 | { | |
3937 | struct ext4_inode_info *ei = EXT4_I(inode); | |
3938 | struct super_block *sb = inode->i_sb; | |
3939 | struct buffer_head *bitmap_bh = NULL; | |
3940 | struct ext4_prealloc_space *pa, *tmp; | |
3941 | ext4_group_t group = 0; | |
3942 | struct list_head list; | |
3943 | struct ext4_buddy e4b; | |
3944 | int err; | |
3945 | ||
3946 | if (!test_opt(sb, MBALLOC) || !S_ISREG(inode->i_mode)) { | |
3947 | /*BUG_ON(!list_empty(&ei->i_prealloc_list));*/ | |
3948 | return; | |
3949 | } | |
3950 | ||
3951 | mb_debug("discard preallocation for inode %lu\n", inode->i_ino); | |
3952 | ||
3953 | INIT_LIST_HEAD(&list); | |
3954 | ||
3955 | repeat: | |
3956 | /* first, collect all pa's in the inode */ | |
3957 | spin_lock(&ei->i_prealloc_lock); | |
3958 | while (!list_empty(&ei->i_prealloc_list)) { | |
3959 | pa = list_entry(ei->i_prealloc_list.next, | |
3960 | struct ext4_prealloc_space, pa_inode_list); | |
3961 | BUG_ON(pa->pa_obj_lock != &ei->i_prealloc_lock); | |
3962 | spin_lock(&pa->pa_lock); | |
3963 | if (atomic_read(&pa->pa_count)) { | |
3964 | /* this shouldn't happen often - nobody should | |
3965 | * use preallocation while we're discarding it */ | |
3966 | spin_unlock(&pa->pa_lock); | |
3967 | spin_unlock(&ei->i_prealloc_lock); | |
3968 | printk(KERN_ERR "uh-oh! used pa while discarding\n"); | |
3969 | WARN_ON(1); | |
3970 | schedule_timeout_uninterruptible(HZ); | |
3971 | goto repeat; | |
3972 | ||
3973 | } | |
3974 | if (pa->pa_deleted == 0) { | |
3975 | pa->pa_deleted = 1; | |
3976 | spin_unlock(&pa->pa_lock); | |
3977 | list_del_rcu(&pa->pa_inode_list); | |
3978 | list_add(&pa->u.pa_tmp_list, &list); | |
3979 | continue; | |
3980 | } | |
3981 | ||
3982 | /* someone is deleting pa right now */ | |
3983 | spin_unlock(&pa->pa_lock); | |
3984 | spin_unlock(&ei->i_prealloc_lock); | |
3985 | ||
3986 | /* we have to wait here because pa_deleted | |
3987 | * doesn't mean pa is already unlinked from | |
3988 | * the list. as we might be called from | |
3989 | * ->clear_inode() the inode will get freed | |
3990 | * and concurrent thread which is unlinking | |
3991 | * pa from inode's list may access already | |
3992 | * freed memory, bad-bad-bad */ | |
3993 | ||
3994 | /* XXX: if this happens too often, we can | |
3995 | * add a flag to force wait only in case | |
3996 | * of ->clear_inode(), but not in case of | |
3997 | * regular truncate */ | |
3998 | schedule_timeout_uninterruptible(HZ); | |
3999 | goto repeat; | |
4000 | } | |
4001 | spin_unlock(&ei->i_prealloc_lock); | |
4002 | ||
4003 | list_for_each_entry_safe(pa, tmp, &list, u.pa_tmp_list) { | |
4004 | BUG_ON(pa->pa_linear != 0); | |
4005 | ext4_get_group_no_and_offset(sb, pa->pa_pstart, &group, NULL); | |
4006 | ||
4007 | err = ext4_mb_load_buddy(sb, group, &e4b); | |
4008 | BUG_ON(err != 0); /* error handling here */ | |
4009 | ||
4010 | bitmap_bh = read_block_bitmap(sb, group); | |
4011 | if (bitmap_bh == NULL) { | |
4012 | /* error handling here */ | |
4013 | ext4_mb_release_desc(&e4b); | |
4014 | BUG_ON(bitmap_bh == NULL); | |
4015 | } | |
4016 | ||
4017 | ext4_lock_group(sb, group); | |
4018 | list_del(&pa->pa_group_list); | |
4019 | ext4_mb_release_inode_pa(&e4b, bitmap_bh, pa); | |
4020 | ext4_unlock_group(sb, group); | |
4021 | ||
4022 | ext4_mb_release_desc(&e4b); | |
4023 | put_bh(bitmap_bh); | |
4024 | ||
4025 | list_del(&pa->u.pa_tmp_list); | |
4026 | call_rcu(&(pa)->u.pa_rcu, ext4_mb_pa_callback); | |
4027 | } | |
4028 | } | |
4029 | ||
4030 | /* | |
4031 | * finds all preallocated spaces and return blocks being freed to them | |
4032 | * if preallocated space becomes full (no block is used from the space) | |
4033 | * then the function frees space in buddy | |
4034 | * XXX: at the moment, truncate (which is the only way to free blocks) | |
4035 | * discards all preallocations | |
4036 | */ | |
4037 | static void ext4_mb_return_to_preallocation(struct inode *inode, | |
4038 | struct ext4_buddy *e4b, | |
4039 | sector_t block, int count) | |
4040 | { | |
4041 | BUG_ON(!list_empty(&EXT4_I(inode)->i_prealloc_list)); | |
4042 | } | |
4043 | #ifdef MB_DEBUG | |
4044 | static void ext4_mb_show_ac(struct ext4_allocation_context *ac) | |
4045 | { | |
4046 | struct super_block *sb = ac->ac_sb; | |
4047 | ext4_group_t i; | |
4048 | ||
4049 | printk(KERN_ERR "EXT4-fs: Can't allocate:" | |
4050 | " Allocation context details:\n"); | |
4051 | printk(KERN_ERR "EXT4-fs: status %d flags %d\n", | |
4052 | ac->ac_status, ac->ac_flags); | |
4053 | printk(KERN_ERR "EXT4-fs: orig %lu/%lu/%lu@%lu, goal %lu/%lu/%lu@%lu, " | |
4054 | "best %lu/%lu/%lu@%lu cr %d\n", | |
4055 | (unsigned long)ac->ac_o_ex.fe_group, | |
4056 | (unsigned long)ac->ac_o_ex.fe_start, | |
4057 | (unsigned long)ac->ac_o_ex.fe_len, | |
4058 | (unsigned long)ac->ac_o_ex.fe_logical, | |
4059 | (unsigned long)ac->ac_g_ex.fe_group, | |
4060 | (unsigned long)ac->ac_g_ex.fe_start, | |
4061 | (unsigned long)ac->ac_g_ex.fe_len, | |
4062 | (unsigned long)ac->ac_g_ex.fe_logical, | |
4063 | (unsigned long)ac->ac_b_ex.fe_group, | |
4064 | (unsigned long)ac->ac_b_ex.fe_start, | |
4065 | (unsigned long)ac->ac_b_ex.fe_len, | |
4066 | (unsigned long)ac->ac_b_ex.fe_logical, | |
4067 | (int)ac->ac_criteria); | |
4068 | printk(KERN_ERR "EXT4-fs: %lu scanned, %d found\n", ac->ac_ex_scanned, | |
4069 | ac->ac_found); | |
4070 | printk(KERN_ERR "EXT4-fs: groups: \n"); | |
4071 | for (i = 0; i < EXT4_SB(sb)->s_groups_count; i++) { | |
4072 | struct ext4_group_info *grp = ext4_get_group_info(sb, i); | |
4073 | struct ext4_prealloc_space *pa; | |
4074 | ext4_grpblk_t start; | |
4075 | struct list_head *cur; | |
4076 | ext4_lock_group(sb, i); | |
4077 | list_for_each(cur, &grp->bb_prealloc_list) { | |
4078 | pa = list_entry(cur, struct ext4_prealloc_space, | |
4079 | pa_group_list); | |
4080 | spin_lock(&pa->pa_lock); | |
4081 | ext4_get_group_no_and_offset(sb, pa->pa_pstart, | |
4082 | NULL, &start); | |
4083 | spin_unlock(&pa->pa_lock); | |
4084 | printk(KERN_ERR "PA:%lu:%d:%u \n", i, | |
4085 | start, pa->pa_len); | |
4086 | } | |
4087 | ext4_lock_group(sb, i); | |
4088 | ||
4089 | if (grp->bb_free == 0) | |
4090 | continue; | |
4091 | printk(KERN_ERR "%lu: %d/%d \n", | |
4092 | i, grp->bb_free, grp->bb_fragments); | |
4093 | } | |
4094 | printk(KERN_ERR "\n"); | |
4095 | } | |
4096 | #else | |
4097 | static inline void ext4_mb_show_ac(struct ext4_allocation_context *ac) | |
4098 | { | |
4099 | return; | |
4100 | } | |
4101 | #endif | |
4102 | ||
4103 | /* | |
4104 | * We use locality group preallocation for small size file. The size of the | |
4105 | * file is determined by the current size or the resulting size after | |
4106 | * allocation which ever is larger | |
4107 | * | |
4108 | * One can tune this size via /proc/fs/ext4/<partition>/stream_req | |
4109 | */ | |
4110 | static void ext4_mb_group_or_file(struct ext4_allocation_context *ac) | |
4111 | { | |
4112 | struct ext4_sb_info *sbi = EXT4_SB(ac->ac_sb); | |
4113 | int bsbits = ac->ac_sb->s_blocksize_bits; | |
4114 | loff_t size, isize; | |
4115 | ||
4116 | if (!(ac->ac_flags & EXT4_MB_HINT_DATA)) | |
4117 | return; | |
4118 | ||
4119 | size = ac->ac_o_ex.fe_logical + ac->ac_o_ex.fe_len; | |
4120 | isize = i_size_read(ac->ac_inode) >> bsbits; | |
4121 | size = max(size, isize); | |
4122 | ||
4123 | /* don't use group allocation for large files */ | |
4124 | if (size >= sbi->s_mb_stream_request) | |
4125 | return; | |
4126 | ||
4127 | if (unlikely(ac->ac_flags & EXT4_MB_HINT_GOAL_ONLY)) | |
4128 | return; | |
4129 | ||
4130 | BUG_ON(ac->ac_lg != NULL); | |
4131 | /* | |
4132 | * locality group prealloc space are per cpu. The reason for having | |
4133 | * per cpu locality group is to reduce the contention between block | |
4134 | * request from multiple CPUs. | |
4135 | */ | |
4136 | ac->ac_lg = &sbi->s_locality_groups[get_cpu()]; | |
4137 | put_cpu(); | |
4138 | ||
4139 | /* we're going to use group allocation */ | |
4140 | ac->ac_flags |= EXT4_MB_HINT_GROUP_ALLOC; | |
4141 | ||
4142 | /* serialize all allocations in the group */ | |
4143 | mutex_lock(&ac->ac_lg->lg_mutex); | |
4144 | } | |
4145 | ||
4146 | static int ext4_mb_initialize_context(struct ext4_allocation_context *ac, | |
4147 | struct ext4_allocation_request *ar) | |
4148 | { | |
4149 | struct super_block *sb = ar->inode->i_sb; | |
4150 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
4151 | struct ext4_super_block *es = sbi->s_es; | |
4152 | ext4_group_t group; | |
4153 | unsigned long len; | |
4154 | unsigned long goal; | |
4155 | ext4_grpblk_t block; | |
4156 | ||
4157 | /* we can't allocate > group size */ | |
4158 | len = ar->len; | |
4159 | ||
4160 | /* just a dirty hack to filter too big requests */ | |
4161 | if (len >= EXT4_BLOCKS_PER_GROUP(sb) - 10) | |
4162 | len = EXT4_BLOCKS_PER_GROUP(sb) - 10; | |
4163 | ||
4164 | /* start searching from the goal */ | |
4165 | goal = ar->goal; | |
4166 | if (goal < le32_to_cpu(es->s_first_data_block) || | |
4167 | goal >= ext4_blocks_count(es)) | |
4168 | goal = le32_to_cpu(es->s_first_data_block); | |
4169 | ext4_get_group_no_and_offset(sb, goal, &group, &block); | |
4170 | ||
4171 | /* set up allocation goals */ | |
4172 | ac->ac_b_ex.fe_logical = ar->logical; | |
4173 | ac->ac_b_ex.fe_group = 0; | |
4174 | ac->ac_b_ex.fe_start = 0; | |
4175 | ac->ac_b_ex.fe_len = 0; | |
4176 | ac->ac_status = AC_STATUS_CONTINUE; | |
4177 | ac->ac_groups_scanned = 0; | |
4178 | ac->ac_ex_scanned = 0; | |
4179 | ac->ac_found = 0; | |
4180 | ac->ac_sb = sb; | |
4181 | ac->ac_inode = ar->inode; | |
4182 | ac->ac_o_ex.fe_logical = ar->logical; | |
4183 | ac->ac_o_ex.fe_group = group; | |
4184 | ac->ac_o_ex.fe_start = block; | |
4185 | ac->ac_o_ex.fe_len = len; | |
4186 | ac->ac_g_ex.fe_logical = ar->logical; | |
4187 | ac->ac_g_ex.fe_group = group; | |
4188 | ac->ac_g_ex.fe_start = block; | |
4189 | ac->ac_g_ex.fe_len = len; | |
4190 | ac->ac_f_ex.fe_len = 0; | |
4191 | ac->ac_flags = ar->flags; | |
4192 | ac->ac_2order = 0; | |
4193 | ac->ac_criteria = 0; | |
4194 | ac->ac_pa = NULL; | |
4195 | ac->ac_bitmap_page = NULL; | |
4196 | ac->ac_buddy_page = NULL; | |
4197 | ac->ac_lg = NULL; | |
4198 | ||
4199 | /* we have to define context: we'll we work with a file or | |
4200 | * locality group. this is a policy, actually */ | |
4201 | ext4_mb_group_or_file(ac); | |
4202 | ||
4203 | mb_debug("init ac: %u blocks @ %u, goal %u, flags %x, 2^%d, " | |
4204 | "left: %u/%u, right %u/%u to %swritable\n", | |
4205 | (unsigned) ar->len, (unsigned) ar->logical, | |
4206 | (unsigned) ar->goal, ac->ac_flags, ac->ac_2order, | |
4207 | (unsigned) ar->lleft, (unsigned) ar->pleft, | |
4208 | (unsigned) ar->lright, (unsigned) ar->pright, | |
4209 | atomic_read(&ar->inode->i_writecount) ? "" : "non-"); | |
4210 | return 0; | |
4211 | ||
4212 | } | |
4213 | ||
4214 | /* | |
4215 | * release all resource we used in allocation | |
4216 | */ | |
4217 | static int ext4_mb_release_context(struct ext4_allocation_context *ac) | |
4218 | { | |
4219 | if (ac->ac_pa) { | |
4220 | if (ac->ac_pa->pa_linear) { | |
4221 | /* see comment in ext4_mb_use_group_pa() */ | |
4222 | spin_lock(&ac->ac_pa->pa_lock); | |
4223 | ac->ac_pa->pa_pstart += ac->ac_b_ex.fe_len; | |
4224 | ac->ac_pa->pa_lstart += ac->ac_b_ex.fe_len; | |
4225 | ac->ac_pa->pa_free -= ac->ac_b_ex.fe_len; | |
4226 | ac->ac_pa->pa_len -= ac->ac_b_ex.fe_len; | |
4227 | spin_unlock(&ac->ac_pa->pa_lock); | |
4228 | } | |
4229 | ext4_mb_put_pa(ac, ac->ac_sb, ac->ac_pa); | |
4230 | } | |
4231 | if (ac->ac_bitmap_page) | |
4232 | page_cache_release(ac->ac_bitmap_page); | |
4233 | if (ac->ac_buddy_page) | |
4234 | page_cache_release(ac->ac_buddy_page); | |
4235 | if (ac->ac_flags & EXT4_MB_HINT_GROUP_ALLOC) | |
4236 | mutex_unlock(&ac->ac_lg->lg_mutex); | |
4237 | ext4_mb_collect_stats(ac); | |
4238 | return 0; | |
4239 | } | |
4240 | ||
4241 | static int ext4_mb_discard_preallocations(struct super_block *sb, int needed) | |
4242 | { | |
4243 | ext4_group_t i; | |
4244 | int ret; | |
4245 | int freed = 0; | |
4246 | ||
4247 | for (i = 0; i < EXT4_SB(sb)->s_groups_count && needed > 0; i++) { | |
4248 | ret = ext4_mb_discard_group_preallocations(sb, i, needed); | |
4249 | freed += ret; | |
4250 | needed -= ret; | |
4251 | } | |
4252 | ||
4253 | return freed; | |
4254 | } | |
4255 | ||
4256 | /* | |
4257 | * Main entry point into mballoc to allocate blocks | |
4258 | * it tries to use preallocation first, then falls back | |
4259 | * to usual allocation | |
4260 | */ | |
4261 | ext4_fsblk_t ext4_mb_new_blocks(handle_t *handle, | |
4262 | struct ext4_allocation_request *ar, int *errp) | |
4263 | { | |
256bdb49 | 4264 | struct ext4_allocation_context *ac = NULL; |
c9de560d AT |
4265 | struct ext4_sb_info *sbi; |
4266 | struct super_block *sb; | |
4267 | ext4_fsblk_t block = 0; | |
4268 | int freed; | |
4269 | int inquota; | |
4270 | ||
4271 | sb = ar->inode->i_sb; | |
4272 | sbi = EXT4_SB(sb); | |
4273 | ||
4274 | if (!test_opt(sb, MBALLOC)) { | |
4275 | block = ext4_new_blocks_old(handle, ar->inode, ar->goal, | |
4276 | &(ar->len), errp); | |
4277 | return block; | |
4278 | } | |
4279 | ||
4280 | while (ar->len && DQUOT_ALLOC_BLOCK(ar->inode, ar->len)) { | |
4281 | ar->flags |= EXT4_MB_HINT_NOPREALLOC; | |
4282 | ar->len--; | |
4283 | } | |
4284 | if (ar->len == 0) { | |
4285 | *errp = -EDQUOT; | |
4286 | return 0; | |
4287 | } | |
4288 | inquota = ar->len; | |
4289 | ||
256bdb49 ES |
4290 | ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS); |
4291 | if (!ac) { | |
4292 | *errp = -ENOMEM; | |
4293 | return 0; | |
4294 | } | |
4295 | ||
c9de560d AT |
4296 | ext4_mb_poll_new_transaction(sb, handle); |
4297 | ||
256bdb49 | 4298 | *errp = ext4_mb_initialize_context(ac, ar); |
c9de560d AT |
4299 | if (*errp) { |
4300 | ar->len = 0; | |
4301 | goto out; | |
4302 | } | |
4303 | ||
256bdb49 ES |
4304 | ac->ac_op = EXT4_MB_HISTORY_PREALLOC; |
4305 | if (!ext4_mb_use_preallocated(ac)) { | |
c9de560d | 4306 | |
256bdb49 ES |
4307 | ac->ac_op = EXT4_MB_HISTORY_ALLOC; |
4308 | ext4_mb_normalize_request(ac, ar); | |
c9de560d AT |
4309 | |
4310 | repeat: | |
4311 | /* allocate space in core */ | |
256bdb49 | 4312 | ext4_mb_regular_allocator(ac); |
c9de560d AT |
4313 | |
4314 | /* as we've just preallocated more space than | |
4315 | * user requested orinally, we store allocated | |
4316 | * space in a special descriptor */ | |
256bdb49 ES |
4317 | if (ac->ac_status == AC_STATUS_FOUND && |
4318 | ac->ac_o_ex.fe_len < ac->ac_b_ex.fe_len) | |
4319 | ext4_mb_new_preallocation(ac); | |
c9de560d AT |
4320 | } |
4321 | ||
256bdb49 ES |
4322 | if (likely(ac->ac_status == AC_STATUS_FOUND)) { |
4323 | ext4_mb_mark_diskspace_used(ac, handle); | |
c9de560d | 4324 | *errp = 0; |
256bdb49 ES |
4325 | block = ext4_grp_offs_to_block(sb, &ac->ac_b_ex); |
4326 | ar->len = ac->ac_b_ex.fe_len; | |
c9de560d | 4327 | } else { |
256bdb49 | 4328 | freed = ext4_mb_discard_preallocations(sb, ac->ac_o_ex.fe_len); |
c9de560d AT |
4329 | if (freed) |
4330 | goto repeat; | |
4331 | *errp = -ENOSPC; | |
256bdb49 | 4332 | ac->ac_b_ex.fe_len = 0; |
c9de560d | 4333 | ar->len = 0; |
256bdb49 | 4334 | ext4_mb_show_ac(ac); |
c9de560d AT |
4335 | } |
4336 | ||
256bdb49 | 4337 | ext4_mb_release_context(ac); |
c9de560d AT |
4338 | |
4339 | out: | |
4340 | if (ar->len < inquota) | |
4341 | DQUOT_FREE_BLOCK(ar->inode, inquota - ar->len); | |
4342 | ||
256bdb49 | 4343 | kmem_cache_free(ext4_ac_cachep, ac); |
c9de560d AT |
4344 | return block; |
4345 | } | |
4346 | static void ext4_mb_poll_new_transaction(struct super_block *sb, | |
4347 | handle_t *handle) | |
4348 | { | |
4349 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
4350 | ||
4351 | if (sbi->s_last_transaction == handle->h_transaction->t_tid) | |
4352 | return; | |
4353 | ||
4354 | /* new transaction! time to close last one and free blocks for | |
4355 | * committed transaction. we know that only transaction can be | |
4356 | * active, so previos transaction can be being logged and we | |
4357 | * know that transaction before previous is known to be already | |
4358 | * logged. this means that now we may free blocks freed in all | |
4359 | * transactions before previous one. hope I'm clear enough ... */ | |
4360 | ||
4361 | spin_lock(&sbi->s_md_lock); | |
4362 | if (sbi->s_last_transaction != handle->h_transaction->t_tid) { | |
4363 | mb_debug("new transaction %lu, old %lu\n", | |
4364 | (unsigned long) handle->h_transaction->t_tid, | |
4365 | (unsigned long) sbi->s_last_transaction); | |
4366 | list_splice_init(&sbi->s_closed_transaction, | |
4367 | &sbi->s_committed_transaction); | |
4368 | list_splice_init(&sbi->s_active_transaction, | |
4369 | &sbi->s_closed_transaction); | |
4370 | sbi->s_last_transaction = handle->h_transaction->t_tid; | |
4371 | } | |
4372 | spin_unlock(&sbi->s_md_lock); | |
4373 | ||
4374 | ext4_mb_free_committed_blocks(sb); | |
4375 | } | |
4376 | ||
4377 | static int ext4_mb_free_metadata(handle_t *handle, struct ext4_buddy *e4b, | |
4378 | ext4_group_t group, ext4_grpblk_t block, int count) | |
4379 | { | |
4380 | struct ext4_group_info *db = e4b->bd_info; | |
4381 | struct super_block *sb = e4b->bd_sb; | |
4382 | struct ext4_sb_info *sbi = EXT4_SB(sb); | |
4383 | struct ext4_free_metadata *md; | |
4384 | int i; | |
4385 | ||
4386 | BUG_ON(e4b->bd_bitmap_page == NULL); | |
4387 | BUG_ON(e4b->bd_buddy_page == NULL); | |
4388 | ||
4389 | ext4_lock_group(sb, group); | |
4390 | for (i = 0; i < count; i++) { | |
4391 | md = db->bb_md_cur; | |
4392 | if (md && db->bb_tid != handle->h_transaction->t_tid) { | |
4393 | db->bb_md_cur = NULL; | |
4394 | md = NULL; | |
4395 | } | |
4396 | ||
4397 | if (md == NULL) { | |
4398 | ext4_unlock_group(sb, group); | |
4399 | md = kmalloc(sizeof(*md), GFP_NOFS); | |
4400 | if (md == NULL) | |
4401 | return -ENOMEM; | |
4402 | md->num = 0; | |
4403 | md->group = group; | |
4404 | ||
4405 | ext4_lock_group(sb, group); | |
4406 | if (db->bb_md_cur == NULL) { | |
4407 | spin_lock(&sbi->s_md_lock); | |
4408 | list_add(&md->list, &sbi->s_active_transaction); | |
4409 | spin_unlock(&sbi->s_md_lock); | |
4410 | /* protect buddy cache from being freed, | |
4411 | * otherwise we'll refresh it from | |
4412 | * on-disk bitmap and lose not-yet-available | |
4413 | * blocks */ | |
4414 | page_cache_get(e4b->bd_buddy_page); | |
4415 | page_cache_get(e4b->bd_bitmap_page); | |
4416 | db->bb_md_cur = md; | |
4417 | db->bb_tid = handle->h_transaction->t_tid; | |
4418 | mb_debug("new md 0x%p for group %lu\n", | |
4419 | md, md->group); | |
4420 | } else { | |
4421 | kfree(md); | |
4422 | md = db->bb_md_cur; | |
4423 | } | |
4424 | } | |
4425 | ||
4426 | BUG_ON(md->num >= EXT4_BB_MAX_BLOCKS); | |
4427 | md->blocks[md->num] = block + i; | |
4428 | md->num++; | |
4429 | if (md->num == EXT4_BB_MAX_BLOCKS) { | |
4430 | /* no more space, put full container on a sb's list */ | |
4431 | db->bb_md_cur = NULL; | |
4432 | } | |
4433 | } | |
4434 | ext4_unlock_group(sb, group); | |
4435 | return 0; | |
4436 | } | |
4437 | ||
4438 | /* | |
4439 | * Main entry point into mballoc to free blocks | |
4440 | */ | |
4441 | void ext4_mb_free_blocks(handle_t *handle, struct inode *inode, | |
4442 | unsigned long block, unsigned long count, | |
4443 | int metadata, unsigned long *freed) | |
4444 | { | |
26346ff6 | 4445 | struct buffer_head *bitmap_bh = NULL; |
c9de560d | 4446 | struct super_block *sb = inode->i_sb; |
256bdb49 | 4447 | struct ext4_allocation_context *ac = NULL; |
c9de560d AT |
4448 | struct ext4_group_desc *gdp; |
4449 | struct ext4_super_block *es; | |
4450 | unsigned long overflow; | |
4451 | ext4_grpblk_t bit; | |
4452 | struct buffer_head *gd_bh; | |
4453 | ext4_group_t block_group; | |
4454 | struct ext4_sb_info *sbi; | |
4455 | struct ext4_buddy e4b; | |
4456 | int err = 0; | |
4457 | int ret; | |
4458 | ||
4459 | *freed = 0; | |
4460 | ||
4461 | ext4_mb_poll_new_transaction(sb, handle); | |
4462 | ||
4463 | sbi = EXT4_SB(sb); | |
4464 | es = EXT4_SB(sb)->s_es; | |
4465 | if (block < le32_to_cpu(es->s_first_data_block) || | |
4466 | block + count < block || | |
4467 | block + count > ext4_blocks_count(es)) { | |
4468 | ext4_error(sb, __FUNCTION__, | |
4469 | "Freeing blocks not in datazone - " | |
4470 | "block = %lu, count = %lu", block, count); | |
4471 | goto error_return; | |
4472 | } | |
4473 | ||
4474 | ext4_debug("freeing block %lu\n", block); | |
4475 | ||
256bdb49 ES |
4476 | ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS); |
4477 | if (ac) { | |
4478 | ac->ac_op = EXT4_MB_HISTORY_FREE; | |
4479 | ac->ac_inode = inode; | |
4480 | ac->ac_sb = sb; | |
4481 | } | |
c9de560d AT |
4482 | |
4483 | do_more: | |
4484 | overflow = 0; | |
4485 | ext4_get_group_no_and_offset(sb, block, &block_group, &bit); | |
4486 | ||
4487 | /* | |
4488 | * Check to see if we are freeing blocks across a group | |
4489 | * boundary. | |
4490 | */ | |
4491 | if (bit + count > EXT4_BLOCKS_PER_GROUP(sb)) { | |
4492 | overflow = bit + count - EXT4_BLOCKS_PER_GROUP(sb); | |
4493 | count -= overflow; | |
4494 | } | |
4495 | bitmap_bh = read_block_bitmap(sb, block_group); | |
4496 | if (!bitmap_bh) | |
4497 | goto error_return; | |
4498 | gdp = ext4_get_group_desc(sb, block_group, &gd_bh); | |
4499 | if (!gdp) | |
4500 | goto error_return; | |
4501 | ||
4502 | if (in_range(ext4_block_bitmap(sb, gdp), block, count) || | |
4503 | in_range(ext4_inode_bitmap(sb, gdp), block, count) || | |
4504 | in_range(block, ext4_inode_table(sb, gdp), | |
4505 | EXT4_SB(sb)->s_itb_per_group) || | |
4506 | in_range(block + count - 1, ext4_inode_table(sb, gdp), | |
4507 | EXT4_SB(sb)->s_itb_per_group)) { | |
4508 | ||
4509 | ext4_error(sb, __FUNCTION__, | |
4510 | "Freeing blocks in system zone - " | |
4511 | "Block = %lu, count = %lu", block, count); | |
4512 | } | |
4513 | ||
4514 | BUFFER_TRACE(bitmap_bh, "getting write access"); | |
4515 | err = ext4_journal_get_write_access(handle, bitmap_bh); | |
4516 | if (err) | |
4517 | goto error_return; | |
4518 | ||
4519 | /* | |
4520 | * We are about to modify some metadata. Call the journal APIs | |
4521 | * to unshare ->b_data if a currently-committing transaction is | |
4522 | * using it | |
4523 | */ | |
4524 | BUFFER_TRACE(gd_bh, "get_write_access"); | |
4525 | err = ext4_journal_get_write_access(handle, gd_bh); | |
4526 | if (err) | |
4527 | goto error_return; | |
4528 | ||
4529 | err = ext4_mb_load_buddy(sb, block_group, &e4b); | |
4530 | if (err) | |
4531 | goto error_return; | |
4532 | ||
4533 | #ifdef AGGRESSIVE_CHECK | |
4534 | { | |
4535 | int i; | |
4536 | for (i = 0; i < count; i++) | |
4537 | BUG_ON(!mb_test_bit(bit + i, bitmap_bh->b_data)); | |
4538 | } | |
4539 | #endif | |
4540 | mb_clear_bits(sb_bgl_lock(sbi, block_group), bitmap_bh->b_data, | |
4541 | bit, count); | |
4542 | ||
4543 | /* We dirtied the bitmap block */ | |
4544 | BUFFER_TRACE(bitmap_bh, "dirtied bitmap block"); | |
4545 | err = ext4_journal_dirty_metadata(handle, bitmap_bh); | |
4546 | ||
256bdb49 ES |
4547 | if (ac) { |
4548 | ac->ac_b_ex.fe_group = block_group; | |
4549 | ac->ac_b_ex.fe_start = bit; | |
4550 | ac->ac_b_ex.fe_len = count; | |
4551 | ext4_mb_store_history(ac); | |
4552 | } | |
c9de560d AT |
4553 | |
4554 | if (metadata) { | |
4555 | /* blocks being freed are metadata. these blocks shouldn't | |
4556 | * be used until this transaction is committed */ | |
4557 | ext4_mb_free_metadata(handle, &e4b, block_group, bit, count); | |
4558 | } else { | |
4559 | ext4_lock_group(sb, block_group); | |
4560 | err = mb_free_blocks(inode, &e4b, bit, count); | |
4561 | ext4_mb_return_to_preallocation(inode, &e4b, block, count); | |
4562 | ext4_unlock_group(sb, block_group); | |
4563 | BUG_ON(err != 0); | |
4564 | } | |
4565 | ||
4566 | spin_lock(sb_bgl_lock(sbi, block_group)); | |
4567 | gdp->bg_free_blocks_count = | |
4568 | cpu_to_le16(le16_to_cpu(gdp->bg_free_blocks_count) + count); | |
4569 | gdp->bg_checksum = ext4_group_desc_csum(sbi, block_group, gdp); | |
4570 | spin_unlock(sb_bgl_lock(sbi, block_group)); | |
4571 | percpu_counter_add(&sbi->s_freeblocks_counter, count); | |
4572 | ||
4573 | ext4_mb_release_desc(&e4b); | |
4574 | ||
4575 | *freed += count; | |
4576 | ||
4577 | /* And the group descriptor block */ | |
4578 | BUFFER_TRACE(gd_bh, "dirtied group descriptor block"); | |
4579 | ret = ext4_journal_dirty_metadata(handle, gd_bh); | |
4580 | if (!err) | |
4581 | err = ret; | |
4582 | ||
4583 | if (overflow && !err) { | |
4584 | block += count; | |
4585 | count = overflow; | |
4586 | put_bh(bitmap_bh); | |
4587 | goto do_more; | |
4588 | } | |
4589 | sb->s_dirt = 1; | |
4590 | error_return: | |
4591 | brelse(bitmap_bh); | |
4592 | ext4_std_error(sb, err); | |
256bdb49 ES |
4593 | if (ac) |
4594 | kmem_cache_free(ext4_ac_cachep, ac); | |
c9de560d AT |
4595 | return; |
4596 | } |